• Journal of the Korean Ceramic Society
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• v.26 no.3
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• pp.381-389
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• 1989

Effects of annealing temperature, time, and atmospehre on the flow characteristics of Atmospheric Pressure Chemical Vapor Deposition-borophosphosilicate glass were investigated. Stable step coverage can be obtained by annealing the BPSG film at 90$0^{\circ}C$ for 30 minutes in N2 atmosphere, but further heat treatment isnot effective. Flow characteristics of the BPSG film was better in steam atmosphere than in N2 atmosphere, and the factors which cause it were analyzed. The concentration of boron in the BPSG film was measured pretty accurately by FTIR spectrum. Boron content in the BPSG film was reduced by annealing treatment. The decrement of boron was greater in steam atmosphere than in the N2 atmosphere. Also it was found from the FTIR spectroscopic analysis that PH3 inhibited the oxidation of B2H6.

• Journal of the East Asian Society of Dietary Life
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• v.3 no.2
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• pp.99-106
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• 1993

The aim of this study is to elevate the efficiency of salting with low salt concentration in order to improve the quality of salted Chinese cabbage. The efficiency of salting was tested with various sub-atmosphere(760mmHg to 0mmHg), temperature(20$^{\circ}C$ and 30$^{\circ}C$), and concentration of salt(3%, 5% and 10%). The salting efficiency was estimated by amounts of juice, calcium elution, sodium penetration and the state of tissue. The amunts of juice eleuted from Chinese cabbage was increased significantly with the decrease of atmosphere and the time to reach the highest amounts was reduced. This tendency was promoted, with increase of salinigy(from 3% to 10%)and the increase of temperature(more juice at 30$^{\circ}C$ than 20$^{\circ}C$). The amounts of eluted calcium from Chinese cabbage tissue during salting under sub-atmosphere was directly proportional to amounts of juice and was inversely proportional to penetrated sodium. The salting time was reduced with elevation of sub-atmosphere. It was desirable to take between 5.5 and 9 hours to salt under the condition of 3% of salting, 20$^{\circ}C$, and 560-0mmHg. It took between 4.4 and 5 hours under 5% of salt and between 4 and 4.5 hours under 10% of salt. However, it was undesirable because the drying phenomenon and the transparency of tissue appeared under 30$^{\circ}C$ and 160-0mmHg.

• Journal of Powder Materials
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• v.3 no.1
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• pp.49-56
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• 1996

The effect of$H_{2}/N_{2}$gas sintering atmosphere on the carbon content and mechanical properties during the metal injection molding process of carbonyl iron-nickel powder was studied. The carbon content of the specimen after debinding in the pure$N_{2}$atmosphere appeared 0.78 wt%. After showing the maximum value of 1.48 wt.% in the debinding atmosphere of 10%$H_{2}/N_{2}$gas mixture, the carbon content of the debinded specimen decreased gradually with increasing the$H_2$content in the$H_{2}/N_{2}$gas mixture. The carbon contents of the sintered specimen were 0.46~0.63wt% in Na gas atmosphere, while they appeared extremely low above 40%$H_{2}/N_{2}$gas atmosphere. The relative sintered density increased abruptly from 88~90% to 93~96% with the addition of Ni, while the density nearly unchanged above 2% Ni addition. The sintered density increased with increasing the fraction of$H_{2} in H_{2}/N_{2}$gas mixture. Tensile strength and hardness increased, and elongation decreased with increasing carbon and Ni content. In spite of high carbon content of 0.63 wt%, the superior elongation value of 10% was shown.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.

• The Korean Journal of Ceramics
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• v.6 no.4
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• pp.396-400
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• 2000

Dielectric and piezoelectric properties of Pb$_0.9$La$_0.1$TiO$_3$ ceramics were investigated as a function of grain size. Sintering atmosphere was controlled with changing the kind of atmospheric powder and its amount. It was confirmed that dielectric and piezoelectric of Pb$_0.9$La$_0.1$TiO$_3$ were strongly influenced by the sintering atmosphere. Relative dielectric constant of Pb$_0.9$La$_0.1$TiO$_3$ which was sintered in PbO-deficient atmosphere made by Pb$_0.9$La$_0.1$TiO$_3$ powder, increased with the grain size. However, the dielectric constant of the samples sintered in the PbO-sufficient atmosphere made by PbZrO$_3$ powder was slightly decreased with the grain size. Piezoelectric d$_33$ constant of Pb$_0.9$La$_0.1$TiO$_3$ also showed a different trend, depending on the sintering atmosphere. It was almost constant in the range of grain size of 1.3~2.3 $\mu$m when the samples were sintered in the PbO-sufficient atmosphere, while it intensively decreased with the grain size in the case of the PbO-deficient condition.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.47-51
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• 2006

Among Solar activities' events, the geomagnetic storms are believed to cause the largest atmospheric effects. The geomagnetic storm is a complex process of solar wind/magnetospheric origin. It is well known to affect severely on the ionosphere. However, this effect of this complex process will maybe act at various altitudes in the atmosphere, even including the lower layer and the neutral middle atmosphere, particularly the stratosphere. Nowadays, the GPS-derived ZTD (zenith tropospheric delay) can be transformed into the precipitable water vapor (PWV) through a function relation, and further has been widely used in meteorology, especially in improving the precision of Numerical Weather Prediction (NWP) models. However, such geomagnetic effects on the atmosphere are ignored in GPS meteorology applications. In this paper, we will investigate the geomagnetic storms' effects on the middle atmosphere and troposphere (0-100km) by GPS observations and other data. It has found that geomagnetic storms' effect on the atmosphere also appears in the troposphere, but the mechanism to interpret correlations in the troposphere need be further studied.

• Nuclear Engineering and Technology
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• v.34 no.4
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• pp.323-330
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• 2002

Various types of compounds were tested with the aspects of decomposition and formation of residue in a $CO_2$ or 7H$_2$+93$N_2$ atmosphere. The evaporation temperature range of each compound was determined from thermogravimetric curve. Decomposition of dicarbon amide, stearic acid, acrowax and zinc stearate was studied by thermogravimetry in $CO_2$ or in 7H$_2$+93$N_2$ atmosphere. All compounds were decomposed in $CO_2$ atmosphere at lower than 40$0^{\circ}C$, but the residue, ZnO remained for zinc stearate. ZnO did not decompose in $CO_2$ atmosphere up to 130$0^{\circ}C$, but reduced into Zn metal and disappeared in the temperature range of $600^{\circ}C$ to 120$0^{\circ}C$ in 7H$_2$+93$N_2$ atmosphere. The effect of residue, which trapped in closed pores of sintered pellet, on the thermal stability was studied using the resintering test at 1$700^{\circ}C$ in 7H$_2$+93$N_2$ atmosphere. In the case of oxidative sintered pellet with admixing zinc stearate, the cavity formation accompanied with a density drop after resintering is due to the pressure of the Zn gases trapped in the isolated pores.

• Journal of the Korean institute of surface engineering
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• v.55 no.4
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• pp.215-221
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• 2022

In the present work, copper oxide thin films were formed by heat-treatment method with different temperatures and atmosphere, e.g., at 200 ~ 400 ℃; in air and Ar atmosphere. The morphological, electrical and optical properties of the thermally fabricated Cu oxide films were analyzed by SEM, XRD, and UV-VIS spectrometer. Thereafter, photoelectrochemical properties of the thermal copper oxide films were analyzed under solar light (AM 1.5, 100 mW/cm²). Conclusively, the highest photocurrent was obtained with Cu₂O formed under the optimum annealing condition at 300 ℃ in air atmosphere. In addition, EIS results of Cu oxide formed in air atmosphere showed relatively low resistance and long electron life-time compared with Cu Oxide fabricated in Ar atmosphere at the same temperature. This is because heat-treatment in Ar atmosphere could not form Cu₂O due to lack of oxygen, and thermally formed CuO at high temperature suppressed stability and conductivity of the Cu oxide.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.17-28
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• 1997

This experiment was carried out to investigate the effects of different chilling and packing methods on physico-chernical properties of cold-stored chicken breast and thigh meats. Dehoned chicken breast and thigh meats were chilled either air spray or ice-water immersion method. The chilled meats were either vacuum packed or atmosphere packed, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The pH of both immersion chilled meats and vacuum packed meats were higher than those of their counterparts(P<0.05). The pH of atmosphere packed meats increased as the storage period extended. The moisture contents of vacuum packed meats were remarkably higher than those of atmosphere packed meats. The pH of all treatments decreased as the storage period extended. The shear values of air spray chilled and vacuum packed breast meats were significantly higher than immersion chilled and vacuum packed ones. However, immersion chilled and atmosphere packed breast meats were significantly higher than those of air spray chilled and atmosphere packed breast meats. The shear values of immersion chilled and vacuum packed thigh meats were significantly higher than those of immersion chilled and vacuum packed thigh meats. In atmosphere packed thigh meats, air spray chilling method showed higher shear values than those of immersion chilled thigh meats. In thigh muscle, tenderness values tended to decrease as the storage period extended(P<0.05). Contents of water soluble proteins of vacuum packed and air spray chilled breast and thigh meats were higher than those of their counterparts as the storage period extended(P<0.05). The contents of water soluble proteins significantly decreased as the storage period extended. Salt soluble proteins of atmosphere packed breast and thigh meats were remarkably higher than those of vacuum packed ones(P<0.05). Total lipid contents of atmosphere packed and air spray chilled breast and thigh meats were higher than those of atmosphere packed and immersion chilled meats as the storage period extended. The vacuum packed meats were significantly higher in total lipid contents than those of atmosphere packed meats. The storage period decreased the total lipid contents of cold chicken, Major fatty acids in cold-stored chicken were oleic, palmitic, linoleic and stearic acids, regardless of chilling method. Unsaturated fatty acids of all treatments decreased, but saturated fatty acids increased as the storage period extended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.549-554
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• 2003

This study was conducted to investigate the effect of storage atmosphere sterilization using acidic electrolyzed water for table grapes (Vitis labrusca L.). ‘Campbell Early’ and ‘Sheridan’ grapes were stored at $0^{\circ}C$ for 12 weeks under the atmosphere that was passed through an acidic electrolyzed water for sterilization. Storage atmosphere sterilization using acidic electrolyzed water did not influence on the changes in soluble solids, titratable acidity, soluble tannins, anthocyanins, ethanol, acetaldehyde and organoleptic quality attributes including color, aroma, texture, juiciness and sweetness of both varieties during storage. Growth of bacteria and fungus in grapes during storage, however, was inhibited by storage atmosphere sterilization. These results suggest that the storage atmosphere sterilization using acidic electrolyzed water can be utilized for improving the storage life of table grapes.