• 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.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.25-29
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• 1981

Harvested asparagus, Viking variety, was stored in normal and controlled atmosphere with and without ‘Butts in water’ to extend shelf life of fresh asparagus. Controlled atmosphere storage significantly reduced bacterial soft rot of asparagus. When asparagus was stored in controlled atmosphere in combination with ‘Butts in water’, asparagus spears could be stored over 3 weeks without noticeable soft rot. Texture of stored asparagus, as measured by Instron and fiber analysis, became tougher as the storage time was extended. Increase of fiber content in asparagus was significantly reduced by controlled atmosphere storage and fiber content actually decreased in asparagus stored in controlled atmosphere in combination with ‘Butts in water’. Asparagus stored in controlled atmosphere had markedly less chlorophyll destruction than that in normal atmosphere. Reflectance color values of stored asparagus were closely associated with chlorophyll content in asparagus. Considering all quality factors of stored asparagus, controlled atmosphere in combination with ‘Butts in water’ was the best storage method to maintain overall quality of harvested asparagus over 3 weeks.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.6
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• pp.318-323
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• 2009

The lightweight aggregates made of bottom ash (70 wt%) and dredged soil (30 wt%) were prepared to investigate the property differences at various sintering atmospheres. The green aggregates were sintered at $1150^{\circ}C$ and $1200^{\circ}C$ with oxidized, neutralized and reduced atmospheres. The aggregates sintered with oxidized atmosphere showed a clear border between shell and black core area. However, the aggregates sintered with a reduced atmosphere showed only black core area in the entire cross-section of the aggregates. The black core area of the aggregates sintered with a neutralized atmosphere increased with increasing $N_2$ gas flow rates. It was determined that the sintering atmosphere was similar to that of rotary kiln when the CO gas flow was 100 cc/min to make a reduced atmosphere in tube furnace. The water absorption rates of both aggregates from tube furnace with reduced atmosphere and rotary kiln were very similar to each other.

• Journal of Ginseng Research
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• v.22 no.2
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• pp.73-81
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• 1998

In order to stabilize the price of fresh ginseng by extension of seasonal variation and marketing structure, and to reduce the cost of production by works of intensive and short term, studies were carried out. As fresh ginseng of 4 years old by the MA (modified atmosphere storage) and CA (controlled atmosphere storage) was stored for 12 week at 4$^{\circ}C$, samples were collected after every 1, 2, 3, 4, 6, 8, 12 weeks for processing red ginseng. Chemical characteristics on ginseng steamed red for the quality evaluation are summarized as follows. The composition of free sugar was consisted of fructose, glucose, sucrose, and maltose in fresh ginseng. And small change was revealed in free sugar composition during the storage period. Glucose and sucrose were largely increased in both treatments of MA (modified atmosphere storage) and CA (controlled atmosphere storage) after 4 week, wherein maltose was decreased. Fifteen different amino acids were identified, and total amount of histamine and arginine were over 40%. Phenylalanine was slightly decreased. As the volatile components in control red ginseng, six different ones including triisopropyl benzene were detected. B-1 ($CO_2$ : $O_2$ : N2=6 : 4.90, DF-100) of CA and E-1 (CPP, DF-100) of MA did not shown triisopropyl benzene as the volatile components. And ${\gamma}$-muurolene, guaiaene, and beta-patchoulene were reduced, but the other components showed the trend of increase.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.1
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• pp.22-26
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• 2013

PTCR ceramics of $(Ba_{0.998}Sm_{0.002})TiO_3+0.001MnCO_3+xSiO_2$ (x=1, 2, 3, 4, 5, 6 mol%) were fabricated by solid state method. Disk samples of diameter 5 mm and thickness about 1mm were sintered at $1,290^{\circ}C$ for 2 h in reduced atmosphere of $5%H_2-95%N_2$ followed by re-oxidation at $600^{\circ}C$ for 30 min. in $20%O_2-80%N_2$.and their microstructures and electrical properties were investigated with SEM and Multimeter. The color of sintered samples was strongly dependent on $SiO_2$ content showing that the color of samples with $SiO_2$ of 1~2 mol% was gray but that of samples with $SiO_2$ of 4~6 mol% was changed from gray to blue, which seems to be related with the reduction of samples due to the oxygen vacancies created during the sintering in reduced atmosphere. $SiO_2$ content had a great influence on the microstructure and the electrical properties. With increasing $SiO_2$ content, the grain size of samples increased and the resistivity as well as the resistivity jump ($R_{285}/R_{min}$) decreased, which is considered to be attributed to the resistivity change at grain interior and grain boundary due to the fast mass transfer through $SiO_2$ liquide phase during the sintering. Samples with 2 mol% $SiO_2$ has the resistivity of $202{\Omega}cm$ and the resistivity jump of 3.28. It is expected that $SiO_2$ doped $BaTiO_3$ based PTC ceramics can be used for multilayered PTC thermistor due to the resistance to the sintering in reduced atmosphere.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.6
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• pp.661-669
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• 2002

Rapid tooling technique enables us to make dies and molds that produce prototype parts with the correct material at a substantially reduced cost and time. In this study, experiments on selective laser sintering of tungsten carbide-cobalt mixture were carried out to find optimal sintering conditions that will be applied to rapid metal tooling. The experiments were carried out within an air, an argon and a nitrogen atmosphere. Coupons of single layer were sintered at various laser powers, scanning speeds and scan spacings. Very severe oxidation took place within an air atmosphere. The oxidation is reduced significantly within an argon and a nitrogen atmosphere. The thickness of the sintered coupons is increased as the energy density, the laser energy Per unit scanned area, is increased. Several multi-layer sintering experiments were also carried out.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.269-274
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• 2001

This paper describes the experimental results on direct selective laser sintering of WC-Co mixture. The experiments were carried out within an air, argon and nitrogen atmosphere. The main problem occurred during sintering within an air atmosphere was oxidation of WC-Co mixture. As the power of laser is increased and scanning speed is decreased, more severe oxidation takes place. Within an argon and nitrogen atmosphere the oxidation is reduced significantly. As the energy density is increased the thickness of the sintered layer is increased.

• Journal of the Korean Ceramic Society
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• v.51 no.1
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• pp.25-31
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• 2014

New green phosphor is synthesized by reducing $LiAlO_2:xEu^{3+}$ phosphors in a low pressure $H_2$ atmosphere. The $LiAlO_2:xEu^{3+}$ prepared by a solid state reaction method is reported as red phosphor. The effect of the reduction treatment on the $LiAlO_2:xEu^{3+}$ on the crystalline phase change and photoluminescence (PL) property are characterized. The reduced phosphor had a broad green light spectrum centered at 524 nm. The PL intensity of the reduced phosphor increased to a maximum at the reduction temperature of $1100^{\circ}C$. The PL intensity decreased with a further increase in the reduction temperature. The crystalline phase constituting the reduced phosphor varied with the temperature. A new crystalline phase $Li_2Al_4O_7$ was observed at $1100^{\circ}C$. The origin of the green-light emission is discussed in relation to the crystalline phase change.

• 한국지구과학회:학술대회논문집
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• 2005.02a
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• pp.115-125
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• 2005

Carbon isotopic composition of a stream (Odaecheon Stream) monitored over 7 months from July 2004 to January 2005 in Gangweon Province ranges from -9.24 to -4.69‰. Strong negative correlation between ${\delta}^{13}C_{DIC}$ and water temperature suggests that temperature is a dominant factor controlling ${\delta}^{13}C_{DIC}$ in the Odaecheon Stream. The variation pattern of ${\delta}^{13}C_{DIC}$ was thought to be caused by fractionation of C isotope between stream water and atmosphere and more fractionation at reduced temperature. More fractionation of C isotope between stream water and atmosphere at reduced temperature resulted in increase of ${\delta}^{13}C_{DIC}$ of stream water in winter compared to summer. Photosynthesis and respiration of aqueous biota seem to affect little in ${\delta}^{13}C_{DIC}$ as indicated by little variation of dissolved oxygen and reverse variation pattern of Eh in the stream and scarce aqueous biota in stream water. pH seems to be controlled by $CO_2{2}$ exchange between stream water and atmosphere. During summer more $CO_2{2}$ exchange between stream water and atmosphere resulted in decrease in pH value.

• 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.