• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.43 no.4
• /
• pp.362-369
• /
• 2007

This paper was studied on the characteristics of acid resistance and thermal shock for epoxy coatings in the strong acidic environment. The exhaust gas system, such as a air preheater, desulfurization equipment, for industrial boiler is damaged by dew point corrosion. To protect the acid corrosion, the coating using nonmetal was applied. The electrochemical polarization test, acid resistance and thermal shock test for epoxy coatings were carried out. And the acid resistance and thermal shock characteristics, aspect, and electrochemical anti-corrosion characteristics for epoxy coatings in the strong acidic environment were considered. The main results are as followings: As the epoxy glass flake coating by acidic thermal shock was damaged to the crack, blistering and elution etc., the current density of epoxy glass flake coating is high. But the damage of epoxy metal complex coating by acidic thermal shock was not occurred. Therefore the characteristics of acid resistance and thermal shock for epoxy metal complex coating is better than those for epoxy glass flake coating.

• Journal of the Korea Institute of Building Construction
• /
• v.12 no.2
• /
• pp.203-210
• /
• 2012

Recently, the interest and demand for large-scale buildings and skyscrapers have been on the rise, and the performance of concrete is an area of high priority. Securing 'mass concrete and high strength concrete' is very important as a key construction technology. For high strength concrete, the high heat of hydration takes place inside the concrete because of the vitality of hydration in cement due to the large amount of powder, and leads to problems such as an increase of thermal stress due to the temperature difference with the outside, which results in cracks and slump loss. For this reason, measures to solve these problems are needed. This study aims to reduce the hydration heat of high strength concrete to control the hydration heat of mass concrete and high strength concrete, by replacing the type of admixture, The purpose of this study is to control the hydration heat of high strength concrete and mass concrete. Our idea for this purpose is to apply not only the types and contents of admixture but also incorporation mixing water to ice-flake. As a result of the test, the use of blast furnace slag and fly ash as admixture, and the use of ice-flake as mixing water can improve the liquidity of concrete and reduce slump loss. Significantly dropping the maximum temperature will contribute greatly to reducing cracks due to hydration heat in mass concrete and high strength concrete, and improve quality.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.34 no.3
• /
• pp.167-173
• /
• 2008

Pearlescent pigments have been widely used in cosmetic applications. Up to date; the most widely used pearl effect pigment is the mica-based pigment, which uses natural mica as the substrate that is in turn coated with metal of oxide interference layer. However, when natural mica is employed as a base material the final product often has a yellowish color, mainly due to the fact that natural mica contains low levels of iron as an impurity[1,2]. This study was focused on developing a pearl pigment which might have a similar sparkling effect as snow. This effect was found to be due to its structure and purity, and this concept was also applied to development of our pearl pigments. More specifically, this invented pearl effect pigments are the mixture of glass-flake and glass-flake coated metal oxides and present the optical properties of snow matrix such as refractive index and particle size, unlike only the glass-flake or glass-flake coated metal oxides to be applied in. Using base material having similar physical properties (refractive index and particle size) as snow matrix as platelet for pearl effect pigments, these invented pigments present a three-dimensional glittering effect of the snow matrix. With this invented figments an applied; we achieved the beauty of snow crystal from makeup products containing these pigments.

• Journal of Animal Science and Technology
• /
• v.45 no.3
• /
• pp.421-432
• /
• 2003

The objective of this study was to examine the effects of processing methods of corn grains on protein and starch degradability in the rumen by three ruminally cannulated dry Holstein cows. The corns for these experiments were untreated; whole corn L(density; 660 g/$\ell$), whole corn H(density; 740 g/$\ell$), and treated by four different types: Ground corn, 3.8 mm, 2.8 mm, and 1.5 mm flaked corn. The results obtained were summarized as follows: For 48 hrs, the protein degradabilities were high in order, ground corn, 1.5 mm, 2.8 mm, and 3.8 mm flaked corn(82.6, 76.5, 64.5, and 33.9%, respectively). Flaked corn grains were degraded lower than ground corn. However, as increasing the processing degree of flaking, the protein degradabilities, from 4 hrs to 48 hrs, were increased. The starch degradabilities on 48 hrs were higher in 1.5 and 2.8 mm flaked corns, ground corn, 3.8 mm flaked corn(99.1, 91.5, 89.5, and 68.9%, respectively) than whole corn L(32.0%) and whole corn H(20.5%)(P<0.05). By increasing the processing degree of flaking, the protein degradabilty between 2.8 mm and 3.8 mm was increased significantly from 68.9% to 91.5%, however, that of 1.5 mm flaked corn, processed thinner, tended to be increased slightly, but was not significantly different. From 12 hrs to 24 hrs, whole corn L was degraded little more than whole corn H in starch, was not significantly different. However, after 48 hr incubation in the rumen, whole corn L was degraded more 50% than whole corn H(P<0.05). The value of degradation parameter “a” of protein was lower in all flaked corns than in ground corn. In contrast, the value of degradation parameter “a” of starch was significantly higher in all flaked corns than in ground corn(P<0.05). It seemed that by flaking the corn grains, starch particles were gelatinized, and then, starch was degraded more rapidly, while protein was degraded more slowly. Referring to these kinds of physical characteristics of grain sources in ruminal degradabilities, it is possible to synchronize the fermentation of nitrogen and carbohydrate sources, in formulating the cattle diets.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 1998.10b
• /
• pp.11-11
• /
• 1998

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2000.04a
• /
• pp.54-54
• /
• 2000

• Journal of the East Asian Society of Dietary Life
• /
• v.11 no.2
• /
• pp.131-139
• /
• 2001

The physicochemical and sensory characteristics of brown rice flakes by different processing conditions such as flaking Process and their heat treatments were investigated to establish the brown rice flake processing procedure. To successfully make the compressed rice grain type flakes, the most appropriate water steeping conditions were 5 hours at 60'C. The brown rice flakes by compressed flaking procedure and heat treatment with microwave toasting showed the best crispiness-texture that tested from textrometer or sensory evaluation, and there was no significant difference between the source of rice varieties. The water absorption index(WAI) of tested flakes were negatively correlated with the water soluble index( WSI) and positively correlated with bowl life. The flakes made by compressed flaking procedure and heat treatment with microwave toasting showed longer bowl life, which is the length of the time that the cereal can retain its crispness after being soaked in milk.

• Tribology and Lubricants
• /
• v.29 no.4
• /
• pp.242-247
• /
• 2013

This study aims to establish the fundamental basis for the design of materials used in high-speed trains, by using a lab-scale dynamometer to evaluate the characteristic behavior of metallic sintered friction materials in relation to the shape of graphite. The test results clearly demonstrate that when flake graphite and granular graphite are added equivalently, the average coefficient of friction is much lower, and it is less influenced by speed variation; moreover, friction wear is observed to be insignificantly low. Adding flake graphite increases the coefficient of friction, which leads to higher friction wear. In addition, the roughness of the disc surface was equivalent regardless of the shape of the graphite.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1999.11a
• /
• pp.57-61
• /
• 1999

The effect of the microstructure of gray cast iron on friction properties was investigated by using a pad-on-disk type friction tester. Cast iron samples used in this investigation were obtained from "step block" castings, which were designed to produce microstructure with different graphite flake morphologies from different cooling rate and solidification rate. Results of this work showed that the gray cast iron disks with long graphite flakes showed less fading. The rotors containing smaller amounts of ferrite showed higher friction coefficient and better fade resistance than others.an others.

• Journal of the Korean Society of Food Culture
• /
• v.26 no.3
• /
• pp.279-282
• /
• 2011

We evaluated the sensory characteristics of Gangjung base obtained from various manufacturers, using a sensory descriptive analysis. Significant differences were observed for all sensory attributes of Gangjung samples with the exception of 'toothpacking'. Sample A showed high intensities for 'external color', 'external roughness', 'sweetness', 'toasted soybean powder flavor', 'crispness', 'fracturability', 'oiliness', and 'loose particles,' whereas it had low intensities for 'rice flour flavor', 'hardness', and 'toughness' compared to those of other samples. Sample B had more 'sourness', 'butyric acid flavor', 'fermented rice flavor', and 'degree of melting' but lower 'air cell size', 'fracturability', and 'flake roughness'. Sample C showed high intensities for 'expansion', 'hardness', 'crispness', and 'flake roughness', whereas sample D showed low intensities for 'expansion' and 'sourness'. These results indicate that Gangjung base samples are markedly different depending on the manufacturer.