• Journal of Environmental Science International
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• v.15 no.12
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• pp.1171-1175
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• 2006

Deposited road particles (DRPs) were analysed for heavy metal concentrations at four different roads in a city, Korea. The samples were collected using a roadway surface vacuum cleaning vehicle which was commonly used in collecting roadway surface particles. Six particle size ranges were analyzed separately for twelve heavy metal elements (Cd, Cr, Pb, Ni, Al, As, Co, Cu, Fe, Mn, Zn and Hg). At all sampling sites, the high concentration of the heavy metals occurred in the <74um particle size range, which conventional roadway cleaning vehicles do not remove efficiently. The Pb concentration significantly increased with decreasing particle size of DRPs, and other toxic heavy metals (Cd, Cr and Ni) also showed similar results. The heavy metal concentrations in the smaller size fraction of DRPs is important because they are contaminants that are preferentially transported by road runoff during rainfall.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.505-509
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• 2000

The purpose of this study was to evaluate the effects of $Ca(OH)_2$ and $CO_2$ additions on the corrosion of metal coupons(ductile iron, galvanized steel, copper and stainless steel). Corrosion rate and released metal ion concentration of ductile iron and galvanized steel decreased by adjusting alkalinity, calcium hardness and pH with $Ca(OH)_2$ & $CO_2$ additions on copper and stainless steel were less than those on ductile iron and galvanized steel. When ductile iron coupon was exposed to water treated with Ca(OH)$_2$&$CO_2$, additions, the main components of corrosion product formed on its surface were $CaCO_3$ and $Fe_2 O_3 or Fe_2 O_4$ which often reduce the corrosion rate by prohibiting oxygen transport to the metal surface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.265-268
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• 2000

We fabricated an IMI-O polymer containing an imidazole group that could form a complex structure between the monolayer and the metal ions at the air-water interface. Also. the monolayer behavior at the air-water interface and the surface morphology of metal-complexed Langmuir-Blodgett(LB) films were investigated by using Brewster angle microscopy(BAM) and Scanning Maxwell-stress Microscopy(SMM). The difference in the BAM and SMM images between the pure water and the aqueous metal ions is attributed to the interactions of the copolymers with the metal ions at the interface and the consequent change of the monolayer organization.

• Journal of Sensor Science and Technology
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• v.25 no.3
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• pp.178-183
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• 2016

Semiconductor gas sensors based on metal oxide are widely used in a number of applications, from health and safety to energy efficiency and emission control. Nanomaterials including nanowires, nanorods, and nanoparticles have dominated the research focus in this field owing to their large number of surface sites that facilitate surface reactions. Recently, metal oxide hollow structures using soft templates have been developed owing to their high sensing properties with large-area uniformity. Here, we provide a brief overview of metal oxide hollow structures and their gas-sensing properties from the aspects of template size, morphology, and additives. In addition, a gas-sensing mechanism and perspectives are presented.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.147-151
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• 2011

In this study, we prepared graphene by using the modified Hummers-Offeman method and then introduced the metals (Pt, Pd and Fe) for dispersion on the surface of the graphene for synthesis of metal-graphene composites. The characterization of the prepared graphene and metal-graphene composites was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and transmission electron microscopy (TEM). According to the results, it can be observed that the prepared graphene consists of thin stacked flakes of shapes having a well-defined multilayered structure at the edge. And the metal particles are dispersed uniformly on the surface of the graphene with an average particle size of 20 nm.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.434-434
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• 2011

Electrochemical method have been employed in this work to modify the chemical vapour deposited nitrogen doped hydrogen amorphous diamond-like carbon (N-DLC) film to fabricate nickel and copper nano particle modified N-DLC electrodes. The electrochemical behaviour of the metal nano particle modified N-DLC electrodes have been characterized at the presence of glucose in electrolyte. Meanwhile, the N-DLC film structure and the morphology of metal nano particles on the N-DLC surface have been investigated using micro-Raman spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. The nickel nano particle modified N-DLC electrode exhibits a high catalytic activity and low background current, while the advantage of copper modified N-DLC electrode is drawn back by copper oxidizations at anodic potentials. The results show that metal nano particle modification of N-DLC surface could be a promising method for controlling the electrochemical properties of N-DLC electrodes.

• Journal of the Korean institute of surface engineering
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• v.49 no.6
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• pp.575-579
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• 2016

The metal mesh films with thickness of 1.0, 1.5, $2.0{\mu}m$ were prepared by photolithography using Ag, Al, and Cu metals. Every metal films were showed C(111) preferred orientation and Ag showed the lowest resistivity and followed by Al and Cu. The transmittance of almost films were higher than 90%. But, the Ag film with thickness of $2.0{\mu}m$ was delaminated during photolithography process due to low adhesion. So, Cu and Ti metal films were introduced under Ag film to improve adhesion property. The Cu film showed higher adhesion properties compared to Ti film. Furthermore, the Ti films that deposited on Ag film showed higher acid resistance.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.316-320
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• 1995

The incorporation of metal ion into the Langmuir-Blodgett (LB) film of an itaconate copolymer was investigated. The polymer was prepared via radical copolymerization of monooctadecyl itaconate with triethyleneglycol methyl vinyl ether. The metal ions employed were Na+, Cs+, Mg2+, Fe2+, Al3+, and Fe3+. The surface pressure-area isotherms indicated that all the monolayers studied on subphases with metal ions showed more expanded areas than that observed on pure water. The monolayers showed an irreversible collapse behavior. The collapse pressure of the monolayers was low on subphases containing trivalent metal ions. From the FT-IR spectra by reflection and transmission modes, the formation of carboxylate salts and the uprisen orientation of the pendant against substrate surface in the polymer LB film were determined. It was estimated by XPS measurement that ca. 13.1 repeat units of the polymer contain one Na+ ion, while one Mg2+ ion corresponds to 5.9 carboxyls.

• Journal of the Korean institute of surface engineering
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• v.55 no.2
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• pp.38-50
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• 2022

As a low-cost and high-efficiency electrocatalysts with high performance and stability become a key challenge in the development of the practical use of water electrolysis, there is an intense interest in transition-metal oxalate-based materials. Transition-metal oxalate-based catalysts with excellent electrochemical performances have been widely applied in water electrolysis due to its low-cost and ease of synthesis. This review provides a useful summary on the development of transition-metal oxalate as potential catalysts for water electrolysis with a focus on the structural and compositional alteration, role of oxalate anion, and enhanced electrochemical performances.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1145-1150
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• 2005

The aim of this paper is to investigate the effect of surface texturing on metal surface and to understand the potential of friction reduction through micro-scale dimple to fabricate by photolithography on pin-on-disk test using flat-on-flat contact geometry. It was verify that the friction property with respect to the same pitch has been influence on the size of dimple under lubricated sliding contact. Also, we can recognize from Stribeck curve that the friction property has a connection with the size of dimple. It can explain a relationship between the friction coefficient and a dimensionless parameter for lubrication condition. The friction property has been an effect on the size of surface texture on reduction friction, not only because the density of dimple, but also because the ratio of diameter/pitch. This ratio of approximately 0.5 is recommend under the tested friction condition. It suggested that the ratio of d/p is an important parameter for surface texture design.