• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.3-9
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• 1974

The role of added metal oxide in the adherence mechanism of low melting glass to several metal plates such as oxygen free high conducting copper, low carbon steel, chrominum galvanized on copper, and stainless steel was investigated. The metal oxide which added to glass were cupric oxide, ferric oxide, chromic oxide, and stainless steel oxide. The glass to that various metla oxide were added, sealed with several metal plates in the electric furnace at $650^{\circ}C$ for 5 minutes. The results as follows; 1) The interfacial reaction was promoted and strong chemical bonding with glass and metals by which the surface energy was decreased showed excellent sealing by addition of metal oxide. 2) When the interfacial reaction of glass and metals was promoted by addition of metal oxide found out that various adhernece mechanism were related to the sealing. 3) When the amount of metal oxide addition was 3-5% the excellent sealing was achieved.

• Korean Journal of Materials Research
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• v.31 no.8
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• pp.427-432
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• 2021

This study uses silicone monomer, DMA, crosslinking agent EGDMA, and initiator AIBN as a basic combination to prepare hydrogel lenses using fluorine-based perfluoro polyether and iron oxide and zinc oxide nanoparticles as additives. After manufacturing the lens using iron oxide nanoparticles and zinc oxide nanoparticles, the optical, physical properties, and polymerization stability are evaluated to investigate the possibility of application as a functional hydrogel lens material. As a result of this experiment, it is found that the addition of the wetting material containing fluorine changes the surface energy of the produced hydrogel lens, thereby improving the wettability. Also, the addition of iron oxide and zinc oxide nanoparticles satisfies the basic hydrogel ophthalmic lens properties and slightly increases the UV blocking performance; it also increases the tensile strength by improving the durability of the hydrogel lens. The polymerization stability of the nanoparticles evaluated through the eluate test is found to be excellent. Therefore, it is judged that these materials can be used in various conditions as high functional hydrogel lens material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.456-461
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• 2012

The glycerol carbonate was synthesized by glycerol and urea using metal oxide catalysts. The physical properties of the prepared metal oxide catalysts were investigated by X-ray diffraction (XRD), specific surface area analysis (BET), field emission scanning electron microscopy (FE-SEM) and temperature programmed desorption (TPD). In addition, we confirmed the conversion of the glycerol and the yield of the glycerol carbonate according to characteristics of metal oxide catalysts. From XRD and FE-SEM analysis, the crystallite size and crystallinity of metal oxide catalysts decrease with addition of Al. In addition, the Zn-Al mixed metal oxide had higher catalytic activity than the pure ZnO due to decreased side reaction in the synthesis of glycerol carbonate.

• Korean Journal of Materials Research
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• v.28 no.9
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• pp.495-498
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• 2018

Intermetallic compound matrix composites have been expected to be established as high temperature structural components. $Ni_3Al$ is a representative intermetallic alloy, which has excellent ductility even at room temperature by adding certain alloying elements. $Ni_3Al$ matrix composites with aluminum oxide particles, which are formed by the in-situ reaction between the alloy and aluminum borate whiskers, are fabricated by a powder metallurgical method. The addition of aluminum borate whiskers disperses the synthetic aluminum oxide particles during sintering and dramatically increases the strength of the composite. The uniform dispersion of reaction synthesized aluminum oxide particles and the uniform solution of boron in the matrix seem to play an important role in the improvement in strength. There is a dramatic increase in strength with the addition of the whisker, and the maximum value is obtained at a 10 vol% addition of whisker. The $Ni_3Al$ composite with 10 vol% aluminum oxide particles $0.3{\mu}m$ in size and with 0.1 wt% boron powder fabricated by the conventional powder metallurgical process does not have such high strength because of inhomogeneous distribution of aluminum oxide particles and of boron. The tensile strength of the $Ni_3Al$ with a 10 vol% aluminum borate whisker reaches more than twice the value, 930 MPa, of the parent alloy. No third phase is observed between the aluminum oxide and the matrix.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.150-151
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• 2013

Recently, the internal space organization of the building changes to the frame construction and flat slab construction in the wall type structure. And the use of light weight panel changing the internal joint use easily is increased. Therefore, in this research, the length change characteristic that the magnesium chloride addition rate reaches to the magnesium curing body tries to be studied. It could confirm according to the length change specific result that the magnesium chloride amount of addition reaches to the magnesium oxide curing body to expand. And the thing described below was the large-scale expansion the magnesium oxide addition rate 60%. And it showed up as 50, 40, 30, 20, and order of 10s (%). It could look at to form the hydrate of the SEM picture result needle-shaped of the Hardened.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.236-237
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• 2014

Recently, it changes to the frame construction in the wall type structure for the life span improvement of the apartment house of our country. The execution of the light panel increased while the execution of the frame construction increased. Therefore, the density and absorption ratio of the magnesium oxide matrix according to the wood flour amount of addition ratio property try to be analyze for the lightweight of the surface material of the light panel. The test result, the density has been declined as the addition ratio increase of the wood flour. In the case of the water absorption ratio, water absorption ratio has been increased as addition ratio increase of wood flour. However, wood flour addition ratio 15% determined the most appropriate when considering the density and water absorption ratio.

• Corrosion Science and Technology
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• v.23 no.1
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• pp.33-40
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• 2024

The concentration and diffusion coefficient of oxide ion vacancies in the oxide scale formed on Fe-22Cr-0.5Mn ferritic stainless steel with and without molybdenum (Mo) was measured at 800℃ by the electrochemical polarization method. After pre-oxidation for 100 h in ambient air at 800 ℃, the oxide scale on one side was completely removed with sandpaper. A YSZ plate was placed on the side where the oxide scale remained. Platinum (Pt) meshes were attached on the top of the YSZ plate and the side where the oxide scale was removed. Changes in electrical current were measured after applying an electrical potential through Pt wires welded to the Pt meshes. The results were interpreted by solving the diffusion equation. The diffusion coefficient and concentration of oxide ion vacancy decreased by 30% and 70% in the specimen with Mo, respectively, compared to the specimen without Mo. The oxide ion vacancy concentration of chromia decreased due to the addition of Mo.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.26-27
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• 2016

This study is an experiment to know mechanical properties that matrix of the magnesium oxide-based can interior Radon gas absorption and decrease by the addition of Bentonite, Vermiculite, illite having characteristic of the cation-exchange and porous. As a study to examine the possibility was fixed the addition amount of each adsorbent that was added to the 0, 10, 20% of magnesium oxide and magnesium chloride with 25%. Illite, bentonite WB is 45 (wt,%), vermiculite W/B was carried out an experiment to 50 (wt,%).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.52-55
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• 1989

The properties of sintered Ag-SnO$_2$contacts which contain the second oxide were investigated with hardeness, workability, electrical conductivity and are erosion. Ag-SnO$_2$contacts containing ZnO or Bi$_2$O$_3$have most excellent workability and arc erosion endurance.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.297-298
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• 2006

Free-machining agent 'KSX' contains complex calcium oxide is developed. The effect of admix ratio of KSX on mechanical properties and machinability with two different cutting speeds is reported. KSX displays improved machinability without deterioration of mechanical properties up to 0.3mass% addition. It was observed that KSX is effective with a small addition of 0.1mass% at slower cutting speed, and increased of admix ratio is effective at faster cutting speed.