• Journal of the Korean Chemical Society
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• v.11 no.2
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• pp.63-69
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• 1967

The stability constants of lead acetato conplexes were evaluated in various ionic strengths (2.00, 1.00, and 0.75), and at various temperature (15, 20, 25, 30, and $35^{\circ}C$), respectively, by the polarographic and potentiometric method of which Hume and Leden had described. The existence of three complex ions, $PbAc^+$, $PbAc_2$, and $PbAc_3^-$ have been shown in the range of concentration of 0~0.8 mole acetate ion. Referring to values obtained, we have derived the following empirical formula with the stability constant (Kijk), ternperature (Tk) and ionic strength (${\mu}j$). log Kijk = (Ai/${\mu}j^3$+ Bi) / Tk + Ci/${\mu}j^3$ + Di . The deduced and observed stability constants are matched in 5% for the K, and $K_3$, and 20% for the $K_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.187-193
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• 1990

Ganoderma lucidum has been widely used not only as ingredients in herbal medicine but also in pharmacological soft drinks. The author collected for analysis of content of 8 kinds of heavy metal(Cd, pb, Hg, Cu, Mn, Fe, As) in soil and cluture soil in an around the Taegu area including Sang Ju, Non Gong, Keum Ho, and Weol Bae. THe toxic content in Gaoderma lucidum showed relatively low level as in cadmium lead mercury arsenic : 0.8-0.13ppm 0.17-1.43ppm 0.02-0.32ppm 0.01-0.19ppm respectively : in copper mangenese zinc and iron : 0.93-4.29ppm, 0.37-2.18ppm 1.02-1.65ppm, 4.57-11.04ppm those grown in soil showed higher percentages of content than those grown on logs in lead copper zinc and iron by 43.2% 68.6%, 20.3% and 43.2% respectively. The content of heavy metals in those grown in soil and culture soil tended to be higher in the areas near factories of industrial complexes especially in manganese and iron. The content of heavy metals in soil and culture soil appeared lower than the mean values of Korean Soil. No interrelationship was found in the content of heavy metals between those of Ganoderma lucidum grown on logs and those grown in soil. In case of pot cultivation however the mushroom spawns are grown originally in soil which seems to influence the degree of content of heavy metals of media.

• Proceedings of the Microbiological Society of Korea Conference
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• 2000.10a
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• pp.128-135
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• 2000

The thiosulfate reductase gene (PhsABC) from Salmonella typhimurium was expressed in Escherichia coli in order to produce sulfide from inorganic thiosulfate and precipitate metals as metal sulfide complexes. A 5.1-kb DNA fragment containing the native phsABC and a 3.7-kb DNA fragment, excluding putative promoter and regulatory regions were inserted into expression vectors pTrc99A and pJB866, respectively. Upon expression of phsABC, E. coli DH5$\alpha$ harboring the phsABC constructs showed higher thiosulfate reductase activity and produced significantly more sulfide than the control strain (E. coli DH5$\alpha$) under both aerobic and anaerobic conditions. Among the four constructs, E. coli DH5$\alpha$ harboring pSB74 produced the highest level of thiosulfate reductase and removed most of heavy metals from solution under anaerobic conditions. In a mixture of 100 $\mu$M each of cadmium, lead, and zinc, the strain could remove $99\%$ of the total metals from solution within 10 hours. Cadmium was removed first, lead second, and zinc last. In contrast, a negative control did not produce any measurable sulfide and removed very little metals from solution. These results have important implications for removal of metals from wastewater contaminated with several metals.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.5
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• pp.589-597
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• 2016

There are a number of industrial complexes which could be a source of heavy metal (loid)s contamination of arable soil in Gyeongnam province of South Korea. Heavy metal (loid)s accumulation of plant is more related to the concentration of plant available heavy metal (loid)s in arable soil than that of total heavy metal (loid)s. The objectives of this study were 1) to examine heavy metal concentrations in soils located near industrial complexes in Gyeongnam province and 2) to determine the relationship between concentration of plant available heavy metal (loid)s and chemical properties of soil. Soil samples were collected from 85 sites of arable lands nearby 7 industrial complexes in Gyeongnam province. Total heavy metal (loid)s concentration, available heavy metal (loid)s concentration, and chemical properties of collected soils were measured. The mean concentrations of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the soils were $5.8mg\;kg^{-1}$, $1.3mg\;kg^{-1}$, $0.03mg\;kg^{-1}$, $51.5mg\;kg^{-1}$, and $68.7mg\;kg^{-1}$, respectively. Total concentration of Cd and Zn in arable soil located near ${\nabla}{\nabla}$ industrial complex exceeded the warning criteria ($4mg\;kg^{-1}$ and $300mg\;kg^{-1}$ for Cd and Zn, respectively) as described by in the soil environmental conservation Act of Korea. The concentration of plant available heavy metal (loid)s was negatively related to the soil pH and available Pb and Zn concentrations had relatively high correlation coefficient when compared with other heavy metal (loid)s. The concentration of plant available Pb and Zn was negatively related to that of organic matter (OM). Based on the above results, it might be a good soil management to control pH and OM concentration with soil amendments such as lime and compost to reduce phytoavailability of heavy metal (loid)s in arable soil located near industrial complex.

• Journal of environmental and Sanitary engineering
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• v.14 no.3
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• pp.80-89
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• 1999

The ion exchange resins have been synthesized from chlormethyl styrene-1,4-divinyl benzene(DVB) with 1%, 5%, and 10%-crosslinking and macrocyclic ligand of cryptand type by copolymerization method and the adsorption characteristics of uranium(VI), lead(II) and holmium(III) ions have been investigated in various experimental conditions. The correlation between the adsorption characteristics of rare earths and transition metal on the resins and stability constants of complexes with macrocyclic ligand have been examined. The $UO_2^{2+}$ aqueous solutions are not adsorbed on the resins below pH 3.0, but the power of adsorption of $UO_2^{2+}$ increased rapidly above pH 4.0. The adsorption power was in the order of 1%, 10%, and 5%-crosslinked resin, but adsorptive characteristics of resins decreased in proportion to the order of dielectric constants of solvents.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.35-35
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• 2011

The design and preparation of novel dye rotaxanes have gained much interest recently, since such structure usually exhibits peculiar spectral and optical changes. In spite of the promising results to date, increasing pressure remains to develop novel supramolecular structures based on stimuli-responsive systems. This presentation covers the study of inclusion complexes of cyclodextrins and various chromophores, with an emphasis on our most recent outcome of anisotropic hydrogel. In this system, physical gelation prepared from simple mixture of CD and a azo dye is completed through specific host-guest interaction. The obtained hydrogel exhibits respective morphological transitions based on supramolecular assembly and dissociation, leading to either precipitation or a sol-to-gel transition. It can identify different classes of metal ions, and, among them, naked-eye differentiation of lead ion is possible due to the coordination-induced unthreading of dye molecules. Accompanying structural changes were verified by numerous characterization techniques, including 2D-ROESY, HR-MAS, UV-Visible absorption, small-angle X-ray scattering, and induced circular dichroism measurements. Such properties discussed here will find useful in analytical applications, such as metal ion sensing and removal applications.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.1
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• pp.77-82
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• 2000

The stereoselective ligand exchange reaction of trans-$[Co(SS-epm)Cl_2]^+$ and racemic propane-1,2-diamine (rac-pn) produces the complex that is identified as $[CO(N)_6]^{3+}$ type of $[Co(SS-epm)(pn)]^{3+}$ by absorption spectrum. It is conceivable that the reaction mechanism involves substitution and isomerization. The calculated and experimentally determined ratios of the complexed enantiomeric substrates at equilibrium were as follows: $[Co(SS-epm)(pn)]^{3+}$,calcd 32 % / 68 %, exptl 19 % / 81 % R-pn / S-pn. It has been shown that the employment of molecular mechanics calculations as a predictive tool may lead to the design of chiral complexes that may be applied to the separation of racemic mixtures of simple bidentate ligands.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.21-22
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• 2006

Significant progress has been realized in the design and synthesis of light emitting polymers with emission over the whole range of the visible spectrum. However up to seventy-five percent of charge recombination events can lead to triplet states that decay non-radiatively. Following the pioneering work in the field of small molecule organic light emitting devices it has been found that solution processible iridium polymer complexes can be used to harness the wasted triplet energy. In this paper new results concerning electrophosphorescence of solution processible tethered iridium polymer derivatives will be presented. Furthermore our approaches to the design of new high triplet energy conjugated polymer hosts will be reported.

• Macromolecular Research
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• v.15 no.2
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• pp.129-133
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• 2007

Significant progress has been realized in the design and synthesis of light emitting polymers that emit over the entire visible spectrum. However, up to seventy-five percent of charge recombination events can lead to triplet states that decay non-radiatively. Following the pioneering work in the field of small molecule organic light emitting devices, it has been found that solution processible iridium polymer complexes can be used to harness the wasted triplet energy. In this paper, new results with respect to the electrophosphorescence of solution processible tethered iridium polymer derivatives are presented. Furthermore, our approaches to the design of new high triplet energy conjugated polymer hosts are also reported.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.181.4-182
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• 2003

Telomeres are DNA-protein complexes at the ends of chromosomes, which play an essential protective role against DNA degradation and aberrant recombination during cell divisions. Several telomerase inhibitors have been reported as candidates for new antitumor drugs. Among them, 2-thiobenzylpyridines, developed by Geron. Co Ltd. as a telomerase inhibitor, were chosen as lead compounds. Twenty-one pyridine-2- carboxylate derivatives were prepared by the coupling of 6-formyl-2-carboxylic acid with the corresponding phenol, thiophenol, and aniline, substituted with various functional groups. (omitted)