• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1279_1280
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• 2009

Vanadium dioxide(VO2) has been reported to be the most attractive material for thermochromic windows due to its semiconductor-metal phase transition at around $68^{\circ}C$. However, our previous experiment showed it is difficult to grow VO2 thin films directly on glass substrate, whereas thermochromic VO2 thin films were successfully grown on R-cut sapphire substrate. Properties of VO2 thin films on different orientations of sapphire substrates were already reported. Furthermore, VO2 thin films were successfully grown heteroepitaxially on (001) preferred oriented ZnO coated glass. We deposited VO2 thin films using V2O5 targets on substrates with various lattice parameters with same orientation(SrTiO3, MgO, and Sapphire substrate of (001) orientation) by pulsed laser deposition. In this work, we will discuss the effects of lattice misfit, substrate-induced stress and grain size on the properties of VO2 thin films deposited on various substrate materials.

• Journal of the Korean institute of surface engineering
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• v.28 no.5
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• pp.267-275
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• 1995

Electron beam can provide convenient way to heat the substrate during Hollow Cathode Discharge (HCD) ion plating of Ti(C, N)films. Densification of columnar structrue is enhanced by longer duration of electron beam heating(EBH). While strong(111) texture is identified always to be formed, the amount of (200) oriented grains which coherently interfaced with carbide particles of the substrate increased with heating(EBH). In turns, these crystallogaphical change lead to the increase of micro hardness and adhesion of coating. Adhesion of Ti(C, N) films increased more dramatically in case of ASP30 substrate of which carbide particles dispersed more finely than M42. Therefore, it could be concluded that both the density of film and interfacial structure can affect the adhesion property. Overheating of substrate could be resulted in low adhesion resistance due to high residual stress developed in the film.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.171-186
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• 1992

Lipolytic characteristics of candia cylindracea lipase was studied by various triacylglycerols with different fatty acyl chains as substrate. The substrate was emulsified with gum arabic and the rate of hydrolysis was determined by pH stat method. The effects of gum concentration, pH, temperature, and $Ca^{2+}$ ion on the enzyme activities were examined. The results show that the effect of these factors are markedly depending on the structurla nature of substrates. The triolein was the best substrate among tested. Present study demonstrates that for characterization of lipolytic enzymes, it is critically important to select proper substrate and activator.r.

• The Korean Journal of Ceramics
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• v.3 no.2
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• pp.105-109
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• 1997

The effects of surface conditions of the C-2 cemented carbide substrate on the adhesion of diamond film were investigated. The substrates were pretreated for different times with Murakami's reagent and then the acid solution of an H2SO4-H2O2. The adhesion strength was estimated by a peeling area around the Rockwell-A indentation. The cutting performance of the diamond-coated tools was evaluated by measuring flank wears in dry turning of Al-17% Si alloy. The morphology of deposited diamond crystallites was dominated by (111) and (220) surfaces with a cubooctahedral shape. The diamond film quality was hardly affected by the surface conditions of the substrate. The variation of tool life with longer substrate etching times resulted from a compromies between the increase of film adhesion at the interface and the decrease of toughness at the substrate surface. The coated tools were mainly deteriorated by chipping and flaking of the diamond film form a lock of adhesion strength, differently from the wear phenomena of PCD tools.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.620-628
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• 2008

Cadmium sulphide (CdS) thin film, which is used as a window layer of heterojunction solar cell, on the glass substrate was deposited by vacuum evaporation. Effects of deposition conditions such as the source and substrate temperature on electrical and optical properties of CdS films was investigated. As the source temperature was increased, the deposition rate of CdS films was increased. In addition, the optical transmittance and the electrical resistivity of CdS films were decreased as the source temperature was increased. This results were attributed to the increase of excess Cd amount in the film. The crystal structure of CdS films exhibited the hexagonal phase with preferential orientation of the (002) plane. As the substrate temperature was increased, the crystal structure of CdS films was improved and the resistivity of the films was increased due to the decrease of excess Cd in film.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.1
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• pp.42-50
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• 2001

The activity of immobilized cell-support particle aggregates is influenced by physical and biochemical elements, mass transfer, and physiology. Accordingly, the mathematical model discussed in this study is capable of predicting the steady state and transient concentration profiles of the cell mass and substrate, plus the effects of the substrate and product inhibition in an immobilized cell-support aggregate. The overall mathematical model is comprised of material balance equations for the cell mass, major carbon source, dissolved oxygen, and non-biomass products in a bulk suspension along with a single particle model. A smaller bead size and higher substrate concentration at the surface of the particle, resulted in a higher supply of the substrate into the aggregate and consequently a higher biocatalyst activity.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.577-584
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• 1996

Silicon oxide films with high hardness and water repellency were prepared by microwave plasma-enhanced CVD using four kind of organosilicon compound-fluoro-alkyl silane mixtures as source gases. An argon gas was used as a carrier gas for fluoro-alkyl silane. The substrate temperatures during deposition were controlled by resistant heating at a constant value between 50 and $300^{\circ}C$. The hardness of the films increased, but the deposition rate and the contact angle for a water drop decreased with increasing substrate temperature. The number of methoxy groups also affected the water repellency and hardness. The deposited films became more inorganic with increasing substrate temperature because of the thermal dissociation of reactants.

• Journal of the Speleological Society of Korea
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• no.76
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• pp.61-66
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• 2006

The present report is the investigation of the effects of the HIP treatment on plasma-sprayed ceramic coating of $Al_2O_3$, $Al_2O_3-SiO_2$ on the metal substrate. These effects were characterized by phase identification, Vickers hardness measurement, and tensile test before and after HIPing.

• Structural Engineering and Mechanics
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• v.57 no.4
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• pp.703-716
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• 2016

In this paper, we have investigated shear horizontal wave propagation in a layered structure, consisting of granular macromorphic rock (Dionysos Marble) substrate underlying a viscoelastic layer of finite thickness. SH waves characteristics are affected by the material properties of both substrate and the coating. The effects of microstructural parameter "characteristic length" of the substrate, along with heterogeneity, internal friction and thickness of viscoelastic layer are studied on the dispersion curves. Dispersion equation for SH wave is derived. Real and damping phase velocities of SH waves are studied against dimensionless wave number, for different combinations of various parameters involved in the problem.

• Journal of the Korean Ceramic Society
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• v.27 no.4
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• pp.513-520
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• 1990

Diamond film was deposited on Si wafer substrate from a gas mixture of methane, hydrogen and oxygen by microwave plasma-assisted chemical vapor deposition. The effects of the pre-treatments of the substrate and of the oxygen addition on the diamond film synthesis are described. In order to obtain diamond film, the substrate was pre-treated with 3 kinds of methods. When the substrate was ultrasonically vibrated within the ethyl alcohol dispersed with 25${\mu}{\textrm}{m}$ diamond powder, the denset diamond film was deposited. Addition of oxygen in the gas mixture of methane and hydrogen improved the crystallinity of the deposited diamond film and also increased the deposition rate of the diamond film more than two times.