• Corrosion Science and Technology
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• v.8 no.2
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• pp.53-61
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• 2009

In this study, both evaluations by visual imaging for exterior view of coating and by EIS were executed for epoxy primer coated specimens deteriorated by accelerated test, and comparison and analysis were carried out for 2 evaluation methods. In the comparison between total damaged area ratio acquired by image processing method and deterioration point, higher deterioration points were appeared for rusted specimens than for non-rusted specimens. It is attributed that deterioration point per unit area ratio given for rust is higher than for peeling. In the comparison between total damaged area ratio and EIS result, impedance of coating was largely decreased as about TEX>$10^4{\Omega}{\cdot}cm^2$ or less when rust area ratio is more than about 0.1%, and blistering area ratio is more than about 3%. Charge transfer resistance ($R_{ct}$) and double layer capacitance ($C_{dl}$) values were appeared for all specimens except 2 ones, which shows that water is accumulated and steel substrate is corroded at coated film-steel interface. In the comparison between deterioration point and EIS result, more than 10 points as deterioration point were given for specimens of below $10^6{\Omega}{\cdot}cm^2$ of impedance at low frequency. For specimens deteriorated by NORSOK cyclic test, impedance was lowest of all, though deterioration point was not high. It is thought to be attributed that coating system and accelerated deterioration condition of cyclic tested specimens were different from those of main specimens. From the result, it is thought that coating resistance can be relatively more decreased than deterioration degree estimated from exterior view under more severe corrosion environment or in the present of more complex deterioration factors.

• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.728-734
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• 2004

The effect of microstructure of WC-Co substrates which have different WC grain sizes from submicron to 5 $\mu$m on the diamond-substrate adhesion strength was investigated. The substrates were pre-treated by two methods : chemical etching with Murakami's solution and subsequently with $H_2SO_4$, and thermal heat-treatment. The adhesion strength was estimated by degree of peeling after Rockwell indentation. Diamond films of 20 $\mu$m thickness deposited on the heat-treated substrates showed an excellent adhesion strength at the load of 100 kg, which ascribed to the large and elongated WC grains. However, the cutting edge of insert was deformed after heat treatment and the surface morphology of heat treated substrate strongly affected on the surface roughness of the deposited diamond films. On the contrary, the diamond film of 10 $\mu$m in thickness on the chemically etched substrates of average WC grain size over 2 $\mu$m showed good adhesion strength enough not to peel-off under a load of 60 kg. Especially, the substrate of average WC grain size over 5 $\mu$m exhibited much improved reliability of adhesion comparing with the substrate of average grain size under 2 $\mu$m. No substrate deformation was observed in this case after the chemical etching, which is more advantageous and more practical in terms of precious machining than the heat treatment case.

• Journal of Conservation Science
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• v.33 no.6
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• pp.431-442
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• 2017

The purpose of this study is to reveal that coloring status and the degree of damage and the kinds of pigments used in large buddhist painting (Gwaebultaeng) of Tongdosa temple using a scientific analysis methods. It was observed that the physical damage patterns of the Gwaebultaeng were folding, lifting, fading, and peeling. Lead red, cinnabar and organic pigments were used as red pigments. Malachite and atacamite were used as green pigments, azulite and lazulite were blue pigments, lead white and talc were white pigment. It is estimated that overlapping organic pigments on the lead white were used as the yellow pigment and carbon was the black pigment. Through the analysis of the particle status of the pigments, it was confirmed that different types of raw materials were used for the green pigment, and the crystal form was easily distinguishable. Also, the dark blue color and the light blue color differed from each other depending on the size and shape of the raw material particles. Yellow and purple colors were organic pigments which did not have a graininess. The yellow and purple colors were organic pigments free from the graininess, and the pigments of dark red pigments was found to be mixed with the orange color pigments and carbon particles.

• Applied Biological Chemistry
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• v.20 no.3
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• pp.263-269
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• 1977

In order to establish methods of potato processing for mixed cooking with rice as main diet, fundamental research was carried out. On the basis of the previous experiments about potato granules, the yield of products, the process of manufacture, and its economics were determined The results are the following. 1. Yield of products are; (1) 22.2% under dipping treatment in $K_2S_2O_5$ solution. (2) 21.7% under dipping treatment in HCI solution. (3) 20.5% under blanching treatment in boiling water. (4) 19.9% under dipping treatment in boiling $K_2S_2O_5$ solution. (5) 18.7% under dipping treatment in boiling HCI solution. 2. The processing of potatoes is as follows $raw\;materials{\to}peeling{\to}cutting{\to}treatment$ for polyphenol oxidase $inactivation{\to}drying{\to}products$. 3. Potato granules are ordinarily not commercial when compared with rice, however, there are times when it is. When rested laud is planted with potatoes a high yield is produced. This will lower the price of the potato and make it commercial compared with rice.

• Journal of Technologic Dentistry
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• v.34 no.2
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• pp.95-103
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• 2012

Purpose: Fracture strength of all-ceramic 3-unit fixed partial dentures manufactured by CAD/CAM and copy-milling systems were evaluated. Methods: Zirconia cores were made by milling the pre-sintered zirconia block by CAD/CAM or copy milling method followed by subsequent sintering. By building-up the corresponding porcelains on the core, all-ceramic bridges were fabricated, and those were evaluated in comparison with PFM fixed partial denture. Results: During the flexural test of the 3-unit PFM bridge, the porcelain started to chip or break at 507.28(${\pm}62.82$)kgf and the metal framework did not break until the maximum load level of 800kgf which was set in the testing instrument of this study. However, among all-ceramic restoration test groups, Everest(EV) group showed a peeling off or breakage of the porcelain from 365.64(${\pm}64.96$)kgf and the core was broken at 491.77(${\pm}55.62$)kgf. Those values of Zirkonzahn(ZR) were 431.03(${\pm}58.47$)kgf and 602.74(${\pm}48.44$)kgf, respectively. The break strength of the porcelain of PFM(PM) group was significantly higher than that of EV (p<0.05) group and there was no significant difference when comparing to that of ZR (p>0.05). ZR group showed higher break strength than that of EV group however there was no significant difference (p>0.05). The break strength of cores were in the increasing order of EV < ZR < PM (p<0.05). Conclusion: We could find that even though the PM group fractured at much higher value than all-ceramic cores, the breakage values of the porcelain of PM group with crack formation or delamination, which will be regarded as clinical failure, was significantly higher than that of EV group and not significantly higher than that of ZR group at p-values of 0.05. The break strength of ZR group was higher than that of EV group at an insignificant level(p>0.05).

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.84-91
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• 2003

The effects of different dehydration conditions for the removal of ginkgo nut inner coat on peeled ginkgo nuts were examined using physical and sensory methods. Dehydration of ginkgo nuts at $90^{\circ}C$ for 120 min resulted in greater hardness, lightness (L), redness (a), yellowness (b), and firmness. Higher roasted flavor and larger holes were observed with dehydration at $150^{\circ}C$ for 30 min and greater cooked ginkgo flavor and green color with dehydration at $120^{\circ}C$ for 50 min. Based on these findings, dehydration at $120^{\circ}C$ for 50 min was determined as the adequate hot air dehydration condition for the removal of ginkgo nut inner coat. Ginkgo nuts stored at $25^{\circ}C$ maintained overall desirability up to 4 weeks. In ginkgo nuts stored at $4^{\circ}C$, all sensory desirabilities evaluated were reasonably high until 60 days of storage; desirability of appearance decreased moderately at 80 days of storage, and appearance became very undesirable at 180 days. Ginkgo nuts stored at $-18^{\circ}C$ showed little changes until 10 months of storage, but slight decreases in overall desirability, flavor, and texture were noted at 12 months.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.182-189
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• 1980

This experiment was carried out to study on methods of processing the fruit base which is to be used for preparing the fruit yoghurts. Common fruits were compared and peach was chosen among them for this purpose by determing the rate of decrease in hardness during the process of cooking. The maturity, temperature of cooking and methods of peeling were tested to maintain the desirable hardness during the process, and the effects of metallic ion addition on the hardness of the flesh were also studied. The results obtained were as follows. 1. The peaches were keeping the most stable texture during cooking, among common fruits, however the hardness of apples were decreased markedly. Rate of decreases in the flesh hardness were high during the initial stages of cooking then slowered in all fruits tested. 2. Flesh hardness of the peaches were largely affected by the temperature of cooking. And the texture of freeze-stored fruits was severly damaged during thawing, so that could be used only for the limited purposes such as for stirred-type yoghurt. 3. Divalent matallic ions, especially calcium ion, were effective for supporting the flesh hardness of peaches during cooking. 4. The optimal concentration of calcium chloride addition was 0.3%, and this resulted in its final concentration in the product under the legal dosage without any subsquent changes in colour and flavor. 5. The effects of calcium chloride addition were greater in the froms of dices than in those of slices, and in overmature fleshs than in immature ones. 6. Treatment of calcium chloride by soaking the slices or dices of lye-peeled peaches in 0.3% solution was found to be adaptable for the practical process.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.742-750
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• 2006

This study was carried out to investigate the efficacy of two kinds of electrolyzed water with added 0.5% (v/v) citron juice, SAEW-CJ[Strong Acidic Electrolyzed Water with added Citron Juice, pH 2.57, ORP (oxidation-reduction potential) 1,122 mV, HClO 23.05ppm] and LAEW-CJ (Low Alkaline Electrolyzed Water with added Citron Juice, pH 4.67, ORP 997mV, HClO 42.55mV) as storing liquid for peeled taro. During storage at $5^{\circ}C$ until 30 days, SAEW-CJ and LAEW-CJ inhibited the growth of microorganisms more effectively than 0.2% (w/v) APS (aluminium potassium sulfate) and 0.85% (w/v) NaCl did. Total phenolic contents, PRO (polyphenol oxidase) activity, color differences value (${\Delta}E$) and vitamin C contents of peeled taro stored in SAEW-CJ and LAEW-CJ were lower than those stored in 0.2% APS and 0.85% NaCl. The hardness decrement of peeled taro stored in LAEW-CJ was lower than that of the others. In addition, the contents of moisture, crude protein, crude ash, total sugars, and reducing sugars were gradually decreased during storage. However, no difference by peeling methods or immersion liquid was found.