• Korean Journal of Metals and Materials
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• v.50 no.2
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• pp.159-163
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• 2012

A TCO-less ruthenium (Ru) catalytic layer on glass substrate instead of conventional Ru/TCO/ glass substrate was assessed as counter electrode (CE) material in dye sensitized solar cells (DSSCs) by examining the effect of the Ru thickness on the DSSC performance. Ru films with different thicknesses (34, 46, 69, and 90 nm) were deposited by atomic layer deposition (ALD) on glass substrates to replace both existing catalyst and electrode layer. In order to make our comparison, we also prepared an Ru catalytic layer by a similar method on FTO/glass substrate. Finally, we prepared the $0.45cm^2$ DSSC device the properties of the DSSCs were examined by cyclic voltammetry (CV), impedance spectroscopy (EIS), and current-voltage (I-V) method. CV measurements revealed an increase in catalytic activity with increasing film thickness. The charge transfer resistance at the interface between the electrolyte and Rudecreased with increasing Ru thickness. I-V results showed that the energy conversion efficiency increased up to 1.96%. Our results imply that TCO-less Ru/glass might perform as both catalyst and electrode layer when it is used in counter electrodes in DSSCs.

• Journal of the Korean Ceramic Society
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• v.56 no.1
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• pp.71-76
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• 2019

Monochromatic amber phosphor in glasses (PiGs) for automotive LED applications were fabricated with $YAG:Ce^{3+}$, $CaAlSiN_3:Eu^{2+}$ phosphors and Pb-free silicate glass. After synthesis and thickness-thinning process, PiGs were mounted on high-power blue LED to make monochromatic amber LEDs. PiGs were simple mixtures of 566 nm yellow YAG, 615 nm red $CaAlSiN_3:Eu^{2+}$ phosphor and transparent glass frit. The powders were uniaxially pressed and treated again through CIP (cold isostatic pressing) at 200 MPa for 20 min to increase packing density. After conventional thermal treatment at $550^{\circ}C$ for 30 min, PiGs were applied by using GPS (gas pressure sintering) to obtain a fully dense PiG plate. As the phosphor content increased, the density of the sintered body decreased and PiGs containing 30 wt% phosphor had full sintered density. Changes in photoluminescence spectra and color coordination were investigated by varying the ratio of $YAG/CaAlSiN_3$ and the thickness of the plates. Considering the optical spectrum and color coordinates, PiG plates with $240{\mu}m$ thickness showed a color purity of 98% and a wavelength of about 605 nm. Plates exhibit suitable optical characteristics as amber light-converting material for automotive LED applications.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2005.05a
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• pp.293-298
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• 2005

Insulator is being used for material of railroad vehicles as a barrier of heat and noise. But it shows various fire properties in case of fire. In this study, we compared smoke density(Ds) values of rubber foams with the different thickness of glass fiber cross-Al foil according to the standard of ASTM E 662. The result showed that the insulator and barrier property played an important role in decreasing the value of smoke density

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.9
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• pp.788-795
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• 2008

To understand the tensile behaviors of GFRP at low temperature, three types of specimen have been used in this study. Tensile properties and fracture mechanisms for three orthogonal orientations of plain weave glass fabric reinforced epoxy resin laminate were investigated at temperature range of about -30 to $15^{\circ}C$. The tensile properties of axial and edge type specimen decrease slightly with decreasing temperature to $-20^{\circ}C$. However, at $-30^{\circ}C$ the decreases in the tensile properties increased considerably. Below $-20^{\circ}C$, thickness type specimen showed a marked decreases in the tensile properties. It was obvious that the fracture manner of thickness type specimen was adhesive failure at above $-10^{\circ}C$ and a mixed adhesive and cohesive failure at below $-20^{\circ}C$.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.6
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• pp.37-45
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• 2004

In this study, twelve different glass fiber reinforced polymer concrete composite panel specimens with various rib heights and tensile side and reinforced side thickness were produced, and the flexural tests were conducted to figure out the effect of The height and thickness influencing on the flexural properties of composite panel. Test results of the study are presented. Especially, a prediction equation of the ultimate moment based on the strength design method agrees well with the test results, and it is thought to be useful for the corresponding design of cross-section according to various spans as the glass fiber reinforced polymer concrete composite panel is applied for a permanent mold.

• Journal of the Korean Ceramic Society
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• v.29 no.8
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• pp.623-629
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• 1992

The possible use of bioglass as implant materials is due to its biocompatibility to human body. Even if many animal studies for the bioglasses have been performed, their compositional dependences of structures and physical properties are not fully understood. In the present work, physical property measurements such as density and thermal expansion coefficient were carried out for the bioglasses, with substitution of CaO for Na2O in bioglass composition (46.1%SiO2, 24.4%Na2O, 26.9%CaO, 2.6%P2O5:mol%). Hydroxyapatite formation on the glass surface was also examined after reacted in Tris-buffer solution. As CaO was substituted for Na2O, the bond strength between nonbridging oxygen and modifier became stronger to make glass structure rigid, and resulted in increase in density and decrease in thermal expansion coefficient. When the bioglasses were reacted in Tris-buffer solution, hydroxyapatite was formed on the bioglass surface for all prepared glasses in 2 hours, independently on CaO content, and the thickness of hydroxyapatite layer was decreased a little, while the thickness of SiO2 rich layer was decreased sharply with CaO content.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.3
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• pp.69-77
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• 2023

Recently, carbon composites have been applied to various fields. However, carbon composites have not been applied to the fishing vessel field due to its structure standards centered on glass composites. In this study, a structural strength evaluation study was conducted for the application of carbon composites in the fishing vessel field. Hull minimum thickness verification test and hull joint verification test were conducted. Compared to glass composites, the verification was based on equivalent or better performance. The results show that carbon composites can reduce the weight by 20% compared to glass composites. For hull joints, it was necessary to increase the thickness of the joint seam by the thickness of the hull to apply carbon composite. Through this study, a standard for the application of carbon composites to fishing vessel can be established.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.28-32
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• 2015

In this work, we reported fabrication of sealing the glass substrate using laser treatment at low temperature for electrochemical luminescence (ECL) cell. The laser treatment at temperature is using laser diode. The glass substrate sealing by laser treatment tested at 3-10W, 2-5 mm/s for build and tested. The sealing laser treatment method will allow associate coordination between the two glass substrate was enclosed. The effect of laser treatment to sealing the glass substrate was found to have cracks and air gap at best thickness of about 550-600 im for condition 3 W, 3 mm/s. The surface of sealing was roughness which was not influent to electrodes It can reduce the cracks, crevices and air gaps as well, improves the performance viscosity in butter bus bar electrodes. Therefore, it is more effective viscosity between two FTO glasses substrate.

• Structural Engineering and Mechanics
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• v.53 no.1
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• pp.131-146
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• 2015

In the present paper a three-dimensional non-linear truss element and a short computer program for the modeling and predicting approximate lateral deflections in thin glass plates by the method of incremental loading are proposed. Due to the out-of-plane large deflections of thin glass plates compared to the plate thickness within each loading increment, the equilibrium and stiffness conditions are written with respect to the deformed structure. An application is presented on a thin fully tempered monolithic rectangular glass plate, laterally supported around its perimeter subjected to uniform wind pressure. The results of the analysis are compared with published experimental results and found to have satisfactory approximation. It is also observed that the large deflections of a glass plate lead to a part substitution of the bending plate behavior by a tensioned membrane behavior which is favorable.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.5
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• pp.452-458
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• 2004

The major cause of compressor failure is the decrease of oil viscosity due to floodback. In most previous researches on the compressor reliability, the relationship between oil circulation rate and performance or oil viscosity has been studied. Another research topic is flow visualization by using a sight glass on the bottom of a compressor sump area and accumulator. Both oil film thickness and oil level through the sight glass should be assessed for compressor reliability if the oil content of the mixture is small and low viscosity raise poor lubrication of pump bearing. In this study, the compressor reliability was assessed by measuring the viscosity of the mixture and calculating oil film thickness. The analysis of the relationship between bottom shell super heat and oil film thickness at heating operation was peformed. It is concluded that bottom shell superheat does not perfectly stand for the mixture's behavior for a low ambient heating operation and oil film thickness can give more detailed and direct criteria for compressor reliability.