• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.80-84
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• 1976

Two varieties, Lasoda and Sebago potatoes, were studied. Different cooking methods, conventional oven baking at $218^{\circ}C$ and microwave oven baking, have been used to compare the retention of the phenolic compounds. Peeled cortex samples of fresh and cooked potatoes were analyzed for total phenols, phenolic constituents, and moisture loss. Phenolic content was higher in fresh potatoes than in cooked potatoes. Laasoda had higher phenolic content (3. 63mg) than Sebago (1. 71mg). Potatoes with higher phenols (Lasoda) also had larger quantities of chlorogenic acid. There was a greater moisture loss in conventional oven baking potatoes than in microware oven.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.2
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• pp.224-229
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• 1996

Performance characteristics of single cell in phosphoric acid fuel cell were studied for various electrode fabrication parameters such as teflon content, electrode structure, thickness of electrocatalyst layer, platinum content and electrode area. The performance of single cell was decided from the measured voltage-current through a load change. The electrode of 40wt.% teflon exhibited high initial performance of single cell, but in the long term operation, the cell performance of 45 wt.% teflon was better. Also the single cell appeared good performance in case of electrodes with duplicate structure, thin electrocatalyst in thickness, more platinum content, and small area. These results of cell performance were discussed as related to the electrolyte flooding, formation of 3 phase boundary area, internal resistance of electrode, and microstructure of electrode.

• Journal of Microbiology
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• v.39 no.3
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• pp.195-201
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• 2001

The effect of moisture content an the reductive dechlorination of polychlorinated biphenyls and population dynamics of dechlorinating microorganisms was investigated in sediments spiked with Aroclor 1248. In sediment slurry with an overlying water layer, dechlorination ensued after a 4-week lag period and reduced the average number of chlorines per biphenyl from 3.91 to 3.15 after 48 weeks. In the sediments of reduced moisture content, however, dechlorination occurred after a lag period of 12 weeks and decreased the average number of chlorines per biphenyl to only 3.62, and the dechlorination rate was also slower. When the population size of dechlorinators, methanogens, and sulfate-reducing bacteria was determined by the most probable number techniques, however, no difference was found between the slurry and the low-moisture sediments, except for methanogens. The growth of dechlorinating populations coincided with the end of the lag period and they then increased by 3 orders of magnitude in two conditions. Specific growth rate of dechlorinators showed little difference between the slurry and the low-moisture sediments; however, growth yield was high in the sediments of reduced moisture content. The reduction of sediment moisture decreased the dechlorination rate and extent of PCBs but did not inhibit the growth of PCB dechlorinators.

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.117-121
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• 2001

Microstructure of abaxial leaf surface and carbohydrate content of propagules grown in different culture conditions such as heterotrophic, mixotrophic and autotrophic carbon source were investigated. In the leaves of propagules which were grown in the green house, autotrophic and mixotrophic conditions, wax layer was observed, but in the leaves of the heterotrophic propagules, it was not observed. Size and number of stomata of the leaves in the heterotrophic condition was larger and more numerous than that of autotrophic propagules. Especially, stomata of the leaves in the autotrophic condition was similar to the leaves of plant grown in green house. Carbohydrate content was higher in photoautotrophic condition than that in mixotrophic and heterotrophic culture. Also, Free sugar content showed higher in photoautotrophic propagules than that in mixotrophic and heterotrophic culture. In all the culture conditions, content of glucose were higher than that of other free sugars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.19
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• pp.52-58
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• 1975

During the germination of soybean (variety Peongyang: Glycine max L.) which was treated by hypochlorite and standard procedure. fructose content was highest and followed by glucose and galactose. Fructose. glucose and galactose decreased as germination period was longer. in the standard procedure. When hypochlorite was treated the fructose content was highest but galactose was almost negligible. and as the period of treatment was longer. fructose content decreased. The sucrose content increased until 96 hours and decreased thereafter. Over the whole period. the germinated soybean treated by hypochlorite showed higher sugar content than standard procedure. Raffinose decreased and disappeared after 96 hours in the standard procedure. and it didn't show up after 48 hours when treated by hypochlorite. Stachyose decreased in both case.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.3
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• pp.8-12
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• 2009

According to a previous study, talc as a coating pigment can improve the viscosity and the water retention of coating color, the compressibility of coating layer, and hence gravure printability. Talc is also well known for its larger particle size than other pigments, which implies that less binder may be need due to its smaller specific surface area. This study investigated the possibility of reducing binder content for matte grade paper. Coating color was prepared with the Cotalc-2000, which showed the best properties in the previous study. The binder content was varied and the effect of binder content on the physical properties of coated paper and the gravure printability was investigated. It was shown that binder content could be reduced when talc was used as a coating pigment. The reduction in binder content did not influence gloss, roughness and the print density of coated paper but showed improvement in paper porosity, compressibility and missing dot.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.4
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• pp.223-229
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• 2023

This work was intended to investigate the effects of Zn content on microstructure and hardness of discontinuous precipitates (DPs) produced by continuous cooling (CC) in Mg-8%Al-X%Zn alloys with 0%, 0.5% and 1% of Zn contents (wt%). The DPs in the alloys possessed a wide range of (α+β) interlamellar spacings, which is attributed to the different transformation temperatures during CC. The higher Zn content resulted in the lower level of interlamellar spacings of the DPs, along with thinner and larger volume fraction of β phase layer in the DPs. It is noted that the DPs in the alloy with higher Zn content exhibited higher hardness, and that the ratio of increase in hardness of the DPs to that of the as-cast state was also increased with increasing Zn content. The reason was discussed on the basis of microstructural differences of the DPs in the Mg-8%Al-X%Zn alloys.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.2
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• pp.49-55
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• 2011

The failure of electronic instruments is mostly caused by heat and shock. This shock causes the crack initiation at the solder joint interface of PCB component which is closely related with the formation of intermetallic compound(IMC). The Ag content in Pb-free Sn-xAg-0.5Cu solder alloy used in this study was 1.0, 1.2 and 3.0 wt.%, respectively. After soldering with PCB component, isothermal aging was performed to 1000 hrs. The growth of IMC layer was observed during isothermal aging. The drop impact property of solder joint was evaluated by impact bending test method. The solder joint made with the solder containing lower Ag content showed better impact bending property compared with that with higher Ag content. On the contrary to this result, the solder joint made with solder containing higher Ag content showed better impact bending property after aging. It should be caused by the formation of fine $Ag_3Sn$, which relieved the impact. It showed consequently the different effect of fine $Ag_3Sn$ and coarse $Cu_6Sn_5$ particles formed in the IMC layer on the impact bending property.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.519-532
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• 2019

The objectives of this study were to evaluate the effects of shelling ratio and resin content on the properties of bamboo oriented strand board (BOSB) from betung (Dendrocalamus asper) and to determine the correlation between the results of dynamic and static bending tests. Strands were steam-treated at $126^{\circ}C$ for 1 h under 0.14 MPa pressure and followed by washing with 1% NaOH solution. Three-layer BOSB with the core layer perpendicular to the surface was formed with shelling ratios (face:core ratio) of 30:70; 40:60; 50:50; 60:40 and binded with 7% and 8% of phenol formaldehyde (PF) resin with the addition of 1% of wax. The evaluation of physical and mechanical properties of BOSB was conducted in accordance with the JIS A 5908:2003 standard and the results were compared with CSA 0437.0 standard for commercial OSB (Grade O-1). Non-destructive testing was conducted using Metriguard Model 239A Stress Wave Timer which has a wave propagation time from 1 to $9,999{\mu}s$ and a resolution of $1{\mu}s$. BOSB with 8% resin content showed better physical and mechanical properties than those with 7% resin content. The increase of the face layer ratio improved the strength of BOSB in parallel direction to the grain. The results suggested that shelling ratio of 50:50 could be used as a simple way to reduce PF resin requirements from 8% to 7% and to meet the requirements of CSA 0437.0 standard. The results of non-destructive and destructive tests showed a strong correlation, suggesting that non-destructive test can be used to estimate the bending properties of BOSB.

• Journal of Conservation Science
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• v.34 no.6
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• pp.557-568
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• 2018

The manufacturing techniques were studied by investigating a precise analysis on wall structure, features of materials and the painting layer of the bracket mural paintings at Daeungbojeon Hall in Naesosa temple. The wall frame is a single-branch structure, and The mural paintings are composed of 3 layers which are a support layer, a finishing layer and a painting layer. The support layer and the finishing layer are an earth wall that sand and clay such as Quartz, Feldspar, and etc. are mixed. The support and the finishing layers have a combination of medium particle sand and smaller than fine particle sand in the approximate ratios of 0.8:9.2 and 6:4, respectively. Therefore, the aforementioned ratio of sand with medium or large particles is relatively higher in the finishing layer than the support layer. As a result of a precise analysis on the painting layer, it has a relatively thick ground layer for painting which is maximum $456.15{\mu}m$ by using Celadonite or Glauconite and the paintings were colored by using pigments such as Atacamite, Kaolinite or Halloysite, Oxidized steel, and etc. on it. The manufacturing style and the painting techniques of an earth wall are included in the category of the Joseon Dynasty style that have been studied up to now, but the facts that the finishing layer has a high content of sand and a middle layer and chopped straw have not been identified. These are remarkable points in terms of structure and materials, and can be crucial in the evaluation of the state of conservation of mural paintings or preparation of a conservation plan.