• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.361-368
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• 2006

The purpose of this study is to invent the preparation technique of the foam-floater used as a level gauge of liquefied petroleum gas (LPG) tank under high pressure, which has not only closed pores but also has under 5 wt% changingrate in case of depositing 72 h in room-temperature LPG. In pressure-resistance and deposition experiment, the prepared foam-floaters with different sulfur (325 Mesh and 400 Mesh) and foaming agent (dinitrosopentamethylenetetramin; DPT and azodicarbonamide; AC) had a marginal difference in its weight changing-rate. However, the prepared floater with sulfur 400 Mesh and the foaming agent AC had smaller pores and higher closed pore-rate. Under $50kg_f/cm^3$ hydraulic pressure, the floater with medium thermal (MT) carbon showed a lower weight changing-rate than semi reinforcing furnace (SRF) carbon. Providing a post-treatment to the prepared floater, the hardness and the pressure-resistance of the inner pore-wall of floater were increased. Prepared floaters having a specific gravity below 0.30 were distorted and broken, and other floaters with a specific gravity above 0.35 were not useful as a floater because of the low buoyancy. Therefore, it was considered that the floaters with a specific gravity between 0.3~0.35 are the most useful as a floater under $50kg_f/cm^3$ pressure-resistance.

• Food Science and Preservation
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• v.17 no.1
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• pp.36-41
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• 2010

Fermentation characteristics of yakju prepared with addition of Opuntia ficus indica were examined, with respect to the nature and concentration of additional added materials. The pH level began to decrease after the secondary brewing stage and the total acid content increased during fermentation. The level of reducing sugars in yakju prepared with Opuntia ficus indica increased at the first brewing stage and then slowly decreased after 4 days of fermentation. The ethanol content of supplemented yakju rapidly increased during the initial 6 days of fermentation, to a maximum content of 17.1% after 14 days. The free sugar content was higher in yakju fermented with Opuntia ficus indica stem compared with fruit. The level of organic acids increased as the amount of Opuntia ficus indica material increased. Organic acid level increased during fermentation and lactic acid was the main organic acid in yakju fermented with Opuntia ficus indica. Sixteen volatile compounds were found by GC-MS in supplemented yakju. The most prominent volatile component was iso-amyl alcohol, followed by butyl alcohol and methyl esters. The DPPH radical-scavenging activity of yakju fermented with Opuntia ficus indica stem was higher than when yakju was prepared with fruit. Sensory scores of yakju fermented with 20% (w/v) fruit and 10% (w/v) stem were greater than those of yakju prepared by other treatments.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.12
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• pp.802-807
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• 2015

This paper describes the development of a piezoelectric level switch, which aims to effectively monitor the level status in high ambient temperatures. In order to adjust the impedance near the resonant frequency and temperature characteristics, the effect of the case and backing layer materials on its performance was analyzed using the finite element method (FEM). The suggested prototype new level switch has three heat-sink plates attached to SUS bar of 230 mm long, and case of PEEK which contains PZT sensing part. To illustrate the validity of this level switch, 10 samples are prepared and investigated the sensing performance through the high and low temperature ambient.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.389-398
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• 2000

Photocatalytic removal of benzene from air was examined using titanium dioxide photocatalyst films prepared on soda lime glass(50$\times$50$\times$2 mm) by spin coating and chemical vapor deposition. For the measurement of photocatalytic reactivity titanium dioxide coated glass was placed into a batch reactor and concentration of benzene in the reactor was set to abuot 100 ppm, and then illuminated with UV. It was found that catalytic reactivity of titanium dioxide films increased with the increase of titanium dioxide film thickness and then level off beyond a certain film thickness. UV absorption by the films showed the similar trend. The formation of stoichiometric amount of carbon dioxide was confirmed by measurement of carbon dioxide concentration in the reactor. In general spin coated films revealed better photocatalytic reactivity than chemically deposited one within the experimental ranges covered in this study. Morphology and crystal structure of prepared films were investigated by XRD and SEM and they showed significant difference between spin coated films and CVD films. Highest quantum efficiency of prepared titanium dioxide photocatalyst was close to 50%.

• Proceedings of the Korean Printing Society Conference
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• 2007.11a
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• pp.45-57
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• 2007

Properties of newly developed paper from Red Algae Pulp (RAP) were examined. The paper samples were prepared according tomixing RAP fiber with wood fibers, HwBKP and SwBKP, to form a paper with 60 g/$m^{2}$ in weight. It was prepared in three to four different levels of refining degree and pressure so that it can reveal different bulk level in order to clearly compare the opacity at equivalent bulk for each furnish compositions. printability of RAP fiber revealed superior effect on print through repression and initial ink absorption. Those properties are expected to improve further if printability improvement effect due to smoothness improvement is added.

• Journal of the Korean Graphic Arts Communication Society
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• v.25 no.2
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• pp.45-57
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• 2007

Properties of newly developed paper from Red Algae Pulp (RAP) were examined. The paper samples were prepared according tomixing RAP fiber with wood fibers, HwBKP and SwBKP, to form a paper with $60\;g/m^2$ in weight. It was prepared in three to four different levels of refining degree and pressure so that it can reveal different bulk level in order to clearly compare the opacity at equivalent bulk for each furnish compositions. printability of RAP fiber revealed superior effect on print through repression and initial ink absorption. Those properties are expected to improve further if printability improvement effect due to smoothness improvement is added.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.81-86
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• 2002

Yackwa was prepared by the addition of different amounts of egg white, and the samples were analyzed by texture profile analysis, Hunter's colorimetry and sensory evaluation during 5 days of storage. Tn texture profile analysis, the hardness, gumminess and chewiness of Yackwa were increased in all the samples during storage and the texture parameters were increased by increasing egg white level. No significant difference was observed in the lightness, redness and yellowness (p〉0.05), but Hunter's color values were slightly increased during storage in all the samples. In sensory evaluation, no significant difference was observed among the samples during storage except the increase of crispiness and overall acceptance by the addition of egg white. The results showed that Yackwa prepared with 10 g of egg white/(100 g of other ingredients ---약과재료 얼마당 10g 첨가인지 명확히 해야 함) had an acceptable sensory quality.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.04a
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• pp.129-134
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• 2008

Properties of newly developed paper from Red Algae Pulp (RAP) were examined. The paper samples were prepared by mixing RAP fiber with wood fibers, HwBKP and SwBKP, to form a paper with $60g/m^2$ in weight. It was prepared in three to four different levels of refining degree and pressure so that it can reveal different bulk level in order to clearly compare the opacity at equivalent bulk for each furnish compositions. Printability of RAP fiber revealed superior effect on print through repression and initial ink absorption. Those properties are expected to improve further if printability improvement effect due to smoothness improvement is added.

• IMMUNE NETWORK
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• v.2 no.4
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• pp.195-201
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• 2002

Background: IgE is closely related to the development of allergies. However, the poor relationship between the specific IgE level and the severity of allergic diseases suggests the possibility of functionally different IgE isoforms. With this in mind, rat basophilic leukemia (RBL)-2H3 activation was analyzed with each type of rat IgE for two parameters, exocytosis and IL-4 mRNA production. RBL-2H3 has been well documented in the rat mucosal mast cell line. Methods: RBL-2H3 cells sensitized with each kind of rat IgE was activated by cross-linking FcRI with B5 (monoclonal anti-rat IgE mouse IgG antibodies). The RBL-2H3 exocytosis was measured by analyzing the ${\beta}$-hexosaminidase level, and the level of IL-4 mRNA synthesis was analyzed using semiquantitative RT-PCR. Rat IgE, which was produced by a parasite infection (REP), was prepared using either Paragonimus westermani metacercariae (REP-PW) or Anisakis simplex third stage larvae (REP-AS). A rat IgE prototype of IR162 was prepared by a peritoneal injection of immunocytoma. Results: The level of exocytosis showed a linear relationship with the rat IgE concentration when REP-PW or REP-AS was applied. However, it exhibited a biphasic response with IR162. In addition, the time course of heating at $56^{\circ}C$ illustrated the similarity between REP-PW and REP-AS, which differed from that of IR162. In contrast, the level of IL-4 mRNA synthesis in the RBL-2H3 cells with IR162 was comparable to that of either REP-PW or REP-AS. Conclusion: These results suggest that functionally different rat IgE isoforms exists in RBL-2H3 exocytosis.

• YAKHAK HOEJI
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• v.31 no.6
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• pp.394-398
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• 1987

The present paper describes the serum cholesterol level lowering effect of the underground parts of Rosa rugosa(Rosaceae) which have been used in a folkloric medicine for treating diabetics. The methanol extract was shown to lower the serum lipid level against the normal and 1% cholesterol and 0.5% cholic acid diet feeding to rats, respectively. When various fractions prepared from the above methanol extract was administered, the ethyl acetate-soluble fractions lowered the serum cholesterol level most remarkably. And when (+)-catechin from the ethyl acetate-soluble fractions was only administered to them, the serum cholesterol level was significantly lowered to 260$\pm$9.3mg/dl, the decrease of 17% for the control group. Therefore, it is suggested that (+)-catechin is one of the active principles of this plant.