• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.747-750
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• 2006

Research on tripodal complexes has grown in recent decades and has been subject of numerous reports.1-11 The reasons for this interest include their relevance to model functions of metalloenzymes1-3 and their potential applications in catalysis.13-17 The ligand system used most in this category has been tren, the tripodal tetraamine N(CH2CH2NH2)3, and its derivatives.4 The bz3tren is a versatile tetradentate ligand, known to form stable complexes not only with transition metals5-11 including Cu2+, Zn2+ and Co2+ but also anion species.12 However, only few results on the d10 metal complexes with bz3tren have been reported by us10 and others.6,7 As a part of on going efforts, we therefore focus our attention to extend other d10 system that includes heavy metal ions.

• Journal of Powder Materials
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• v.15 no.4
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• pp.292-296
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• 2008

The electromagnetic (EM) wave absorption properties of the $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline powder mixed with 5 to 20 vol% of Ni-Zn ferrites has been investigated in a frequency range from 100MHz to 10GHz. Amorphous ribbons prepared by a planar flow casting process were pulverized and milled after annealing at 425 for 1 hour. The powder was mixed with a ferrite powder at various volume ratios to tape-cast into a 1.0mm thick sheet. Results showed that the EM wave absorption sheet with Ni-Zn ferrite powder reduced complex permittivity due to low dielectric constant of ferrite compared with nanocrystalline powder, while that with 5 vol% of ferrite showed relatively higher imaginary part of permeability. The sheet mixed with 5 vol% ferrite powder showed the best electromagnetic wave absorption properties at high frequency ranges, which resulted from the increased imaginary part of permeability due to reduced eddy current.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2306-2310
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• 2010

Corrosion is a complex series of oxidation/reduction reactions between at the water-metal surfaces and materials in which the water is stored or transported. With respect to the corrosion potential of drinking water, the primary concerns include the potential presence of toxic metals, such as lead and copper; deterioration and damage to the household plumbing, and aesthetic problems such as stained laundry, and bitter taste. This study was performed to evaluate the effects of corrosion inhibitors on corrosion rates, Fe and Cu release concentration in water distribution pipes. Decrease of corrosion rates were strongly related to phosphate corrosion inhibitors. Considering that typical corrosion processes consists of a series of electrochemical reaction at the metal surface in contact with water, corrosion rates were positively correlated with Fe release.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.5
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• pp.449-455
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• 2016

This study provides the finite-element (FE) squeal-model predicting friction-induced noise with respect to several friction materials that have different friction characteristics. The friction curve and the corresponding friction noise were measured for four friction materials (Cu, Ni, Al, Mg) using the pin-on-disk and reciprocating friction system. The slope of the friction curve linearized at the sliding velocity was applied to the FE model. The unstable modes in the complex eigenvalue analysis were shown to correspond to the squeal frequencies that existed in the experiment.

• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.144-148
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• 2009

The transfer of Mn-Superoxide Dismutase (SOD2) gene, complex gene (SA) of CuZnSOD and ascorbate peroxidase (APX), and NDP kinase 2 (NDPK2) gene into Korean 4 cultivars (cvs. Millenium White, Glory Blue, Glory Red, and Glory Purple) and 15 purebred lines of petunia was conducted using Agrobaterium-mediated technique. Two (Wongyo A2-16 and A2-36) of 15 purebred lines and one (cv. Glory Red) of 4 cultivars were effective for the transfer of SOD2 gene. The putative transgenic plants survived on the 2nd selection medium were 124. From PCR analysis, 118 (derived from 4 cultivars and 2 purebred lines) of 124 plants were confirmed to contain marker (npt II ) gene, while 58 of 118 plants did not have target genes. There were no plants with both npt II and SA genes. Twenty seven of 28 SOD2 transgenic plants were re-confirmed as transformants by Sothern analysis. SOD2 and NDPK2 genes were expressed in the transgenic petunias as the ratio of 77.8 to 100.0 % and 23.5%, respectively. T1 seeds were obtained from 36 acclimated transgenic plants (SOD2 34 plus NDPK2) in a glasshouse by self-pollination.

• Journal of the korean society of oceanography
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• v.35 no.2
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• pp.89-97
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• 2000

The pyritization of heavy metals in Lake Shihwa sediments was investigated to determine sedimentary Pyrite-heavy metal associations influenced by various metal fractions, organic carbon, and total reduced sulfur. Parameters indicating the degree of heavy metal pyritization (DTMP) and degree of pyritization (DOP) were used to study the incorporation of heavy metals into the pyrite phase. The DOP levels ranged from 3.28-39.45%, showing wide differences among sampling stations. The levels were greater near the water gate and the center of the lake than near the industrial complex. The spatial pattern of the DOP levels was similar to the S/C ratio and also to the salinity. Based on the measured relationships between DOP and DTMP, heavy metals can be divided into three groups. In the first group was As, which showed a high affinity for pyrite. In the second group were Ni, Co and Cu, which showed a gradual increase in DTMP with increasing DOP. In the final group were Pb, Zn, Mn and Cr, which all showed a low DTMP with constant values with respect to DOP.

• Journal of Soil and Groundwater Environment
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• v.18 no.4
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• pp.32-39
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• 2013

This research focused on the effects of heavy metals on the biomonitoring activity of genetically engineered bioluminescent bacteria, Pseudomonas putida mt-2 KG1206. KG1206 was exposed to single or binary mixtures of different heavy metals as well as soils contaminated with heavy metals. In case of single exposure with different inducer pollutant, the toxicity order was as followings : As(III) > Cd, As(V) >> Cu, Cr(VI). The toxic effects of the binary mixtures was compared to the expected effect based on a simple theory of probabilities. The interactive effects were mostly additive, while in few cases antgonistic and synergistic mode of action was observed for some concentration combinations. No considerable correlation was found between the total metal contents in soils and the bioluminescence activity of each sample. However, statistically significant differences (p = 0.0102) were observed between two groups, classified based on arsenite contamination. These results demonstrate the usage of recombinant bioluminescent microorganism in biomonitoring and the complex interactive effects of metals.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1806-1809
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• 2008

Study that form micro pattern by direct ink jet printing method is getting attention recently. Direct ink jet printing spout fine droplet including nano metal particle by force or air pressure. There is reason which ink jet printing method is profitable especially in a various micro-patterning technology. It can embody patterns directly without complex process such as mask manufacture or screen-printing for existent lithography. In this study, research of a technology that ejects fine droplet form of Pico liter and forms metal micro pattern was carried with inkjet head of piezoelectricity drive system. Droplet established pattern while ejecting consecutively and move on the surface at the fixed speed. Patterns formed in ink are mixed with organic solvent and polymer that act as binder. So added thermal hardening process after evaporate organic solvent at isothermal after printing. I executed high frequency special quality estimation of CPW transmission line to confirm electrical property of manufactured circuit board. We tried a large area printing to confirm application possibility of an ink jet technology.

• Analytical Science and Technology
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• v.8 no.1
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• pp.25-32
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• 1995

Determination method of trace thioglycolate has been studied by adsorptive stripping voltammetry. Copper(II)-thioglycolate complex is adsorbed at the hanging mercury drop electrode and stripped during cathodic scan. Electrolyte was used pH 6.5 phosphate and pH 9.5 borate buffer solutions. Optimal conditions were a copper(II) concentration $1{\times}10^{-4}M$, an adsorption accumulation potential -0.2V, an adsorption accumulation time 60 sec and a scan rate 20mV/sec. A detection limit of $1{\times}10^{-9}M$ thioglycolate was obtained. The method was applied to the determination of thioglycolate in cold wave fluids and depilating creams.

• The Plant Pathology Journal
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• v.18 no.5
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• pp.237-243
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• 2002

A survey of virus infection in garlic plants cultivated in Korea was conducted for three years. Most virus-infected garlic plants (Allium sativum) showed typical symptoms on the leaves such as yellow mosaic, stripes, and distortion. Through immunosorbent electron micro-scopy and RT-PCR analysis, the complex mixtures of viruses including garlic viruses of the genus Allerivirus, gaylic strain of Leek yellow stripe virus of the genus Potyvirus, and Garlic latent virus of the genus Carlavirus were identified in the virus-infected garlic plants. Among these viruses, Allexivirus was the most frequently detect-ed in the regions surveyed. Using sets of differential primers for Allexivirus genomes, two members of the genus were amplified and sequenced from the purified viruses. The deduced amino acid sequences for the coat proteins and the nucleic acid binding proteins of two viruses showed high homologies to Garlic virus A (CarV-A) and Garlic virus D (GarV-D) of Allekivirus. This is the first report of GarV-A and GarV-D in Korea. This suggests that Allexivirus in gavlic plants in Korea was mixed and varied. Phylogenetic analyses showed that the genus Allexivirus was diversi(ied by the processes of accumulation and evolution of viruses in garlic plants due to the long period of repeated vegetative propagation.