• Journal of Powder Materials
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• v.8 no.2
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• pp.117-123
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• 2001

Formation of pores in melt-processed $YBa_2Cu_3O_{7-x}$ (123) oxides and its effect on the microstructure were studied. Spherical pores with a size of a few tens of microns were formed due to the evolution of oxygen gas during melting of a 123 oxide. Some of pores were converted into liquid pockets by liquid filling, but others remained unfilled. The liquid pockets were converted into spherical 123 regions with a lower $Y_2BaCuO_5$ (211)density through the peritectic reaction during subsequent cooling, while the pores were entrapped into the periteictically grown 123 grains. The spherical 123 regions often consists of a residual melt due to the unbalanced peritectically reaction.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.25-31
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• 2010

Combined technique of burner and DOC has been used for regeneration of Diesel Particulate Filter. Experiments has been performed to increase the temperature of engine exhaust gas to burn the collected soot in DPF at all conditions of operation of 3 liter diesel engine. Ignition temperature of soot can be successfully obtained by heats of burner flame and residual fuel oxidation at diesel oxidation catalyst even in the condition of oxygen deficiency. It is found that the load of air compressor and heat loss can be reduced to the level of practical application. It is also found that CO and THC emissions are not increase by additional combustion of regeneration burner.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1688-1691
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• 2007

This paper shows that the boundary image sticking can be prohibited completely by using the vacuum sealing process, which means that the residual impurities such as nitrogen or oxygen can be a critical factor inducing the boundary image sticking. The production of boundary image sticking was checked in the test panel fabricated by the $N_2$ or $O_2$ flow during the vacuum sealing process. As a result, the boundary image sticking did not appear in the case of $N_2flow$, whereas the boundary image sticking was observed in the case of $O_2$ flow even though the test panel was fabricated by the vacuum sealing process.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.326-328
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• 1999

We investigated the effects of residual gas partial pressure on the property of a CeO$_2$ buffer layer on a textured Ni tape, where the buffer layer was deposited by e-beam evaporation. The oxygen partial pressure were varied from 10$^{-7}$ to 10$^{-4}$ Torr. we also changed the surface condition for the surface oxygenation. We'll describe the detail of the resultant textures of the buffer layers and effects of YBCO growth on them

• Economic and Environmental Geology
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• v.24 no.4
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• pp.379-391
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• 1991

The studied Cretaceous granties are widely distributed at the southern Mungyeong area in the southwestern part of Ogcheon Fold Belt. From the mineralogical and geochemical compositions, it is suggested that they show the characteristics of I-type and magnetite-series and formed under the conditions of high oxygen fugacity. The mineral chemistry of plagioclase, alkali feldspar and biotite in the granites by EMPA, was revealed as albite to oligoclase, microcline to microcline perthite and orthoclase perthite, and annite compositions, respectively. The granites have the distribution patterns of enriched LREE and depleted HREE, and show Eu negative anomalies suggesting mainly due to the feldspar fractionation in the residual magma. The geochemical data of Eu, EU/$^*Eu$, Sm and Gd suggest that the granites of the area have more abundant alkali feldspar crystallization than plagioclase. From the geochemical characteristics of Sr/Ba, La/Sm vs. Ce/Yb and other trace element evidences, the granites were the late stage products of differentiation and fractionated from a homogeneous parental granitic magma.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.8-14
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• 1999

A screening has been performed to find hyper-ligninolytic fungi, which degtrade beech and pine lignin extensively in order to broaden the understanding of the ligninolytic enzymes elaborated by various white-rot fungi. One hundred and twenty two ligninolytic strains were selected from decayed woods with a selective medium for screening ligninolytic wood-rotting fungi. Two of them, Phanerochaete sordida YK-624 and YK-472, showed much higher ligninolytic activity and selectivity in beech-wood degradation than typical lignin-degrading fungi, phanerochaete chrysosporium and Coriolus versicolor. They also degraded birch dioxane lignin and residual lignin in unbleached kraft pulp(UKP) much more extensively than P. chrysosporium and C. versicolor. During fungal treatment of beech wood-powder, the fungus strain P. sordida YK-624 showed higher activity of extracellular manganese peroxidase (MnP) in the medium than P. chrysosporium. It also showed MnP activity, which would not be lignin peroxidast during treatment of oxygen-bleached kraft pulp(OKP) and under enzyme-inducing conditin.

• Journal of the Korean institute of surface engineering
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• v.40 no.1
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• pp.39-43
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• 2007

The pure CrN powders oxidized to $Cr_2O_3$ noticeably above $850^{\circ}C$ in air. When these powders were sintered into bulk samples at $1500^{\circ}C$ under 40 atm of $N_2$ pressure, the CrN phase partly changed into the $Cr_2N$ phase, owing to the partial loss of nitrogen from CrN. When the bulk sample was heated at $1000-1200^{\circ}C$ for 100 hr under vacuum, the CrN phase also progressively changed into $Cr_2N$. At the same time, a relatively thin $Cr_2O_3$ layer formed on the bulk sample due to the reaction of chromium with residual oxygen in vacuum.

• Journal of Welding and Joining
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• v.31 no.1
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• pp.38-42
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• 2013

In the welding of aluminum, it is important to provide a stable gas shield to exclude not only oxygen, but any sources of hydrogen, from the arc environment. Common sources of hydrogen are humidity in the air around the arc, moisture in the shielding gas, and residual lubricants on the surface of the welding consumable. Since molten aluminum can absorb seventy times more hydrogen than solid aluminum, as the aluminum cools, it releases hydrogen that then becomes trapped in the form of hydrogen bubbles in the solidifying metal.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.1
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• pp.62-68
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• 1996

In order to establish making process of water atomized iron powder for powder metallurgy, effect of heat treatment condition on change of powder properties and impurities was investigated at each tempeature of $850{\sim}950^{\circ}C$. The results are as follows. Particle morphology of iron powder changed slightly from sphercial type to irregular type and the amount of fine particle decreased more and more with increasing of heat treatment time at each temperature. The flow rate and apparent desity of iron powder also decreased due to particle coalescence in order of $850^{\circ}C$, $950^{\circ}C$, $900^{\circ}C$. Those powder Properties became to decrease particularly at $900^{\circ}C$ in alpha iron region. On the other hand, residual carbon and oxygen contents in iron powder decreased extremely with increasing of heat treatment temperature and time.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.373-385
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• 2004

Irradiation offers an effective and simple means to extend shelf-life of meat and improve processing properties of meat products. Many researches have been conducted to evaluate the effects of irradiation on meats and meat products. There were some interesting reports such as increase of redness and tenderness of meat and decrease of carcinogenic N-nitrosamines and residual nitrite in cured meat products by irradiation. And, the safety of irradiated products have been also studied. Lipid oxidation and off-odor induced by irradiation can be minimized by appropriate controls of irradiation and storage condition such as addition of antioxidants or oxygen exclusion packaging. The objective of this paper is to introduce the effect of gamma irradiation on quality of meats and meat products reported from the previous researches.