• Proceedings of the Korean Vacuum Society Conference
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• 2003.02a
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• pp.187-187
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• 2003

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1491-1494
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• 2008

A novel platinum aminoalkoxide complex, Pt$(dmamp)_2$ has been prepared by the reaction of cis-$(py)_2PtI_2$ with two equivalents of Na(dmamp) (dmamp = 1-dimethylamino-2-methyl-2-propanolate). Single-crystal X-ray crystallographic analysis shows that the Pt(dmamp)2 complex keeps a square planar geometry with each two nitrogen atoms and two oxygen atoms having trans configuration. Platinum films have been deposited on TaN/ Ta/Si substrates by metal organic chemical vapor deposition (MOCVD) using Pt$(dmamp)_2$. As-deposited platinum thin films did not contain any appreciable amounts of impurities except a little carbon. As the deposition temperature was increased, the films resistivity and deposition rate increased. The electrical resistivity (13.6 $\mu\Omega$cm) of Pt film deposited at 400 ${^{\circ}C}$ is a little higher than the bulk value (10.5 $\mu\Omega$cm) at 293 K. The chemical composition, crystalline structure, and morphology of the deposited films were investigated by X-ray photoelectron spectroscopy, X-ray diffraction, and atomic force microscopy.

• Analytical Science and Technology
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• v.18 no.6
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• pp.475-482
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• 2005

The expression of uncertainty applied to the chemical analysis is highly recommended with increasing demands upon the systematic quality assurance and control(QA/QC) with ISO 17025. For the quantification of quality source, 7 major common sources of uncertainty, normally contributing to the quality of the chemical analysis, were selected from QA/QC literatures of chemical analysis. They were classified into repeatability, drift, uncertainty in standards, linearity of calibration, homogeneity, stability of sample, and matrix effect. And, the quantification of the sources by means of measurement uncertainty was proposed as a prerequisite steps for QA/QC. Examples applied to the quantification procedures of modelling, combination and expression of standard uncertainty for the 7 major common sources were presented as a reference guide for QA/QC in chemical analysis.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.51-51
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• 2012

There is a growing interest in innovative chemical synthesis in microreactors owing to high efficiency, selectivity, and yield. In microfluidic systems, the low-volume spatial and temporal control of reactants and products offers a novel method for chemical manipulation and product generation. Glass, silicon, poly(dimethylsiloxane) (PDMS), and plastics have been used for the fabrication of miniaturized devices. However, these materials are not the best due to either of low chemical durability or expensive fabrication costs. In our group, we have recently addressed the demand for economical resistant materials that can be used for easy fabrication of microfluidic systems with reliable durability. We have suggested the use of various specialty polymers such as silicon-based inorganic polymers and fluoropolymer, flexible polyimide (PI) films that have not been used for microfluidic devices, although they have been used for other areas. And inexpensive lithography techniques were used to fabricate Lab-on-a-Chip type of microreactors with differently devised microchannel design. These microreactors were demonstrated for various synthetic reactions: liquid, liquid-gas organic chemical reactions in heterogeneous catalytic processes, syntheses of polymer and non-trivial inorganic materials. The microreactors were inert, and withstand even harsh conditions, including hydrothermal reaction. In addition, various built-in microstructures inside the microchannels, for example Pd decorated peptide nanowires, definitely enhance the uniqueness and performance of microreactors. These user-friendly Lab-on-a-Chip devices are useful alternatives for chemist and chemical engineer to conventional chemical tools such as glass.

• Polymer Science and Technology
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• v.24 no.1
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• pp.3-9
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• 2013

• Proceedings of the Materials Research Society of Korea Conference
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• 2008.05a
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• pp.16.1-16.1
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• 2008

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.636-640
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• 2012

We modify ZnO nanorods with Zn-porphyrin to obtain the improved characteristics of energy transfer, which is further investigated for the applicability to photovoltaic devices. A nitrogen heterocyclic ligand containing a thiol group is covalently grafted onto the surface of finely structured ZnO nanorods with a length of 50-250 nm and a diameter of 15-20 nm. Zn-porphyrin is then attached to the ligand molecules by the mechanism of metalligand axial coordination. The resulting energy band diagram suggests that the porphyrin-modified ZnO nanorods might provide an efficient pathway for energy transfer upon being applied to photovoltaic devices.

• Transactions on Electrical and Electronic Materials
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• v.4 no.3
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• pp.25-28
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• 2003

Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. New polymeric hydrogels based on vinyl ethers have been synthesized by the $\gamma$-initiated polymerization method. In this paper, we have studied the effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on polyvinylether of ethyleneglycol (PVEEG).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.6
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• pp.378-380
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• 2000

The epitaxial $BaTiO_{3}$ thin film was prepared on the MgO substrate by the coating-pyrolysis process using a mixed solution of Ba-naphthenate and Ti-naphthenate. The crystal structure of the epitaxial $BaTiO_{3}$ thin film was characterized by XRD ${\theta}/2{\theta}$ scan and asymmetric {303} rocking curve scan. The epitaxial $BaTiO_{3}$ thin film had the cubic phase with the lattice parameter of a = c = 0.4018 nm.

• Journal of Powder Materials
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• v.17 no.5
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• pp.390-398
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• 2010

Aqueous gold nanoparticle dispersion was synthesized by chemical reduction method using diethanolamine as reducing agent and polyethyleneimine as dispersion stabilizer. The synthesis conditions for the stable dispersion of the gold nanoparticle suspension were determined by changing the amount of the reducing agent and dispersant during the wet chemical synthesis procedures. The face centered cubic lattice structure of the gold nanoparticles was confirmed by using X-ray diffraction and the morphologies of the nanoparticles were observed by transmission electron microscope. The synthesized gold nanoparticle dispersion was concentrated by evaporating the dispersion medium at room temperature followed by the addition of ethyleneglycol as humectant for the increase of the elastic properties to obtain gold nanoparticle inks for direct ink writing process. The line patterns were obtained with the gold nanoparticle inks during the writing procedures and the morphologies of the fine patterns were observed by scanning electron microscope.