• Journal of the Korean Ceramic Society
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• v.31 no.9
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• pp.1021-1029
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• 1994

SiC ultrafine particles of 1, 10, 20 and 30 vol% were dispersed in $\alpha$-Si3N4 matrix and hot-pressed under the condition of 30 MPa at 1800 and 190$0^{\circ}C$ respectively. Physical, mechanical properties and microstructures of sintered Si3N4-SiC nanocomposites were investigated. Flexural strength and density of Si3N4-10 vol% SiC nanocomposites hot-pressed at 190$0^{\circ}C$ represented the 1002 MPa and 97.9%T.D respectively, and it was confirmed as a remarkable improvement of 67% compared to Si3N4 monolith. Fracture toughness was shown as 7.2 MPa.m1/2 when the same composition was hot pressed at 180$0^{\circ}C$. This effect was supposed to be due to the improvement of microstructure by the adequate suppression of the excessive growth of Si3N4 grain with SiC nano-particles.

• Food Science and Preservation
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• v.16 no.6
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• pp.830-837
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• 2009

A total of 24 processed barley samples produced in Korea, 9 split and 15 pressed, were analyzed for protein, $\beta$-glucan, and amylose content whiteness cooking characteristics (water absorption and expansibility) and pasting properties, with respect to the areas in which they were grown. Split and pressed barley products from Japan were compared. Both forms of barley products had similar contents of protein and $\beta$-glucan. Whiteness was higher in pressed barley than in split barley. Split barley produced in Korea had a higher water absorption (342-436%) and expansibility (449-608%) than did pressed barley. Japanese processed barley products were much lower in protein (4.4-6.6%, w/w) and showed a higher whiteness grade than did Korean products. Whiteness of pressed barley ranged from 57.2-68.3 and was higher than that of split barley, but split barley product showed better cooking characteristics than did pressed barley. Japanese products were similar to Korean materials in this respect. A negative correlation was observed between protein content in and whiteness of processed barley products (r=-0.5112, p<0.01). Waxy barley products had a lower pasting temperature, and showed higher breakdown and lower setback than did non-waxy barley products. The pasting properties of Japanese products were different from those of Korean materials. The pasting temperatures of Japanese split and pressed barley were lower, and the setback much higher, than seen with Korean products. The results show that both splitting and pressing efficiently improve the cooking characteristics of barley. The processing of waxy barley was particularly effective.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.560-567
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• 2016

Acid-activated clays (SUPER-DC, DC-A3, and P1) are used for the bleaching of cold-pressed rapeseed oil. In this study we tested the bleaching performance of cold-pressed rapeseed oil according to the different reaction time (20, 40, 60, 80 min) and temperature (40, 80, $120^{\circ}C$). Oil color (lightness, redness, yellowness), pigments (chlorophyll A and carotenoid content) and quality properties (fatty acid composition, tocopherols (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$), and plant sterols (${\beta}$-sitosterol, campesterol, stigmasterol) content) were analyzed. The results showed that bleaching of cold-pressed rapeseed oil with 2% acid-activated clays at $40^{\circ}C$ for 20 min, brightness (L) increased, but redness (a) and yellowness (b) decreased. Bleaching of cold-pressed rapeseed oil with 2% DC-SUPER at $40^{\circ}C$ removed chlorophyll A and carotenoids pigments significantly. In addition, about 50% of total tocopherol content in cold-pressed rapeseed oil was reduced by bleaching. Originally total tocopherol content was 46.62mg/100g in cold-pressed rapeseed oil. But after bleaching, total tocopherol content was 12.67mg/100g (20 min bleaching), 15.31mg/100g (40 min bleaching), and 13.56mg/100g (60 min bleaching). However plant sterols content in cold-pressed rapeseed oil remained unchanged by bleaching. Overall, acid-activated clays were useful for the bleaching of pigmented rapeseed oil.

• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.721-732
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• 2008

Pressed ham was manufactured to investigate the effects of grape seed oil on the quality characteristics of pressed ham. Five treatments were divided based on differences in the amount of grape seed oil added into the pressed ham. For control, 10% of back fat was only added without grape seed oil. For the first treatment, 10% of grape seed oil among the lard component added into the pressed ham was replaced. For the 2nd, 3rd and 4rd treatments, 20%, 30% and 40% of grape seed oil was respectively replaced. Pressed ham manufactured using grape seed oil was vacuum packaged and then stored for 1, 7, 14, 21 and 28 days at 4℃. Samples were analyzed for shear force value, sensory properties, TBARS and fatty acid composition. In the 1, 21 and 28 days of storage, shear force value of grape seed oil treatment (T4) was significantly lower than that of control (P<0.05). No remarkable differences were found in sensory properties among control and grape seed oil treatment groups. The TBARS value was significantly higher in control than in grape seed oil treatment group(T4) at 28 days of storage (P<0.05). The TBARS of control and grape seed oil treatment groups increased significantly as the storage period increased(P<0.05). The linoleic acid(C18:2) content of grape seed oil treatment groups was significantly higher than that of control(P<0.05). But the contents of C10:0～C20:4 were decreased significantly by grape seed oil additive (P<0.05). Saturated and monounsaturated fatty acid content of control was significantly higher than that of grape seed oil treatment groups(P<0.05). Whereas the increase level of grape seed oil additive resulted in the significantly higher polyunsaturated fatty acid content(P<0.05). Based on these findings, we conclude that the sensory properties and lipid oxidation(TBARS) of manufactured pressed ham were not affected by grape seed oil addition. Also, our results indicate that high-quality pressed ham can be manufactured with strengthen of polyunsaturated fatty acid content.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.3
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• pp.223-232
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• 2012

The purpose of this study was to investigate the effect of various thickness of porcelain on shear bond strength between metal coping and porcelain. So, various thickness of feldspathic porcelain and heat-pressed porcelain were built up and compared. 120 metal cube($4{\times}4{\times}4mm$) specimens were prepared. 60 specimens were applied to feldspathic porcelain and the others were applied to heat-pressed porcelain by 1mm, 1.5mm, 2mm, 2.5mm, 3mm and 3.5mm thickness. The measurement of shear bond strength was performed by Instron universal testing machine. The following results were obtained from this study. 1. As thickness of feldspathic porcelain increases, shear bond strength has decreased. Feldspathic specimens with 1mm porcelain thickness were significantly stronger than other feldspathic subgroups. 2. There was no significant difference of shear bond strength according to porcelain thickness in heat-pressed porcelain group. 3. In comparison between subgroups with same thickness, feldspathic porcelain group had stronger shear bond strength than heat-pressed porcelain. There were significant difference between 1mm and 3mm porcelain thickness group. 4. In almost cases, fracture surface was found on both metal and porcelain surfaces. As thickness of porcelain was increased, metal exposure was decreased.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.1
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• pp.31-40
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• 2021

The main stability factors of the pressed powder include hardness and drop stability. In general, for pressed powder with talc, the hardness and drop stability are evenly met and the skin texture is excellent. Recently, more than ever customers are looking for a replacement due to asbestos issue of talc. Therefore, it is urgent to develop a pressed powder formulation without talc that maintains stability and does not lose its sense of use. In this study, experiments were conducted to find the optimal ingredients mixing ratio to make talc-free pressed powder. The characteristics of raw materials used mainly in powder were checked and the ratio was changed, and the lightness and hardness were measured and drop test was conducted. If the natural mica ratio was higher than the synthetic mica or non-coated silica was used instead of the coated silica, the hardness and drop stability were lower than the content containing talc, but the lightness was similar. Conversely, if the synthetic mica ratio was equal to or higher than the natural mica ratio and the coated silica ratio was equal to or higher than the non-coated silica ratio, the hardness and drop stability of the content containing talc were similar, but the lightness was low. It was found that the hardness was higher than the content containing talc, but the drop stability was lower. Therefore, further study of the correlation between hardness and fall stability is also thought to be necessary.

• Journal of the Korean Society of Floral Art and Design
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• no.43
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• pp.101-122
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• 2020

In this paper, the social paradigm is rapidly changing with the expansion of human consciousness, which has emerged as the development of 20th century science and the influence of cutting-edge media as the search for new forms of flower art sculptures. Is becoming. Accordingly, the purpose of this study is to analyze the interaction relationship of the expression elements of environmentally friendly pressed sculptures in the space as interior materials in the space where customer service is provided. (Research method) After deriving the formative expression characteristics of environmentally friendly pressed flower sculptures, and deriving interactive analysis elements between the servicescape space and humans of the pressed flower sculptures through references, service the flower sculptures for 8 installation cases The expression patterns of the interrelationships in the space of the landscape of the landscape were analyzed. (Results) The characteristics of dynamic formation and continuity were emphasized in the environment-friendly pressed sculpture space, and the interaction that the sympathetic reaction to the natural motif element felt as a new experience in space appeared. In the future, commercial spaces can be actively experienced through natural elements, and users can experience active interactions to create differentiated spaces as spaces where humans and humans coexist.

• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.411-416
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• 1987

Thermal expansions and thermal expansion coefficients of cordierite ceramics reinforced by SiC whiskers up to 40 vol. % were investigated. The composite specimens were hot pressed at 1523K for 30 min under 28.5 MPa pressing pressure in Ar atmosphere. Thermal expansions of the hot pressed composites were measured using a differential dilatometer up to 1262 K in air. Thermal expansions and thermal expansion coefficient of the composites increased with SiC whisker content. Thermal expansion behaviors of the composites were well explained by modelling parallel slabs randomly distributed on the whisker plane as the microstructural element of the composites.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.575-582
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• 2000

This investigation was designed to determine whether heat-pressing and/or simulated heat treatments affected the flexure strength and the microstructure of the lithium disilicate glass-ceramic in the IPS Empress 2 system. Four groups of the specimens were prepared as follows: group 1 - as-received material, group 2 - heat-pressed material; group 3 - heat-pressed and simulated initial heat-treated material; group 4 - heat-pressed and the simulated heat-treated material with full firings for a final restoration. The three-point bending test and the scanning elec-tron microscope (SEM) analysis was conducted for the purpose of this study. The flexure strength of group 2 was significantly higher than that of group 1. However, there were no significant differences in strength among group 2, 3, and 4, and between group 1 and 4. The SEM micrographs of the lithium disilicate glass-ceramic showed the closely packed, multi-directionally interlocking microstructure of numerous lithium disilicate crystals protruding from the glass matrix. The crystals of the heat-pressed materials (group 2, 3, and 4) were a little denser and about two times bigger than those of the as-received material (group 1). This change of microstructure is more obviously exhibited particularly between group 1 and 2. However, there was no a marked difference among group 2, 3, and 4 after the heat-pressing procedure. Although there were significant increase of the strength and some changes of the microstructure after the heat-pressing operation, the combination of the heat-pressing and the simulated subsequent heat treatments did not produce the increase of strength of IPS Empress 2 glass-ceramic.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.22-30
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• 1971

Sea mussel Mytilus edulis, world-widely distributed, is a sort of popular food in Korea. The demands of high quality and mass production are not being satisfied since it is usually sun dried. A rapid dehydration and the treatment of food additives to improve the quality of the product seems to be required. In this paper, the effect of antioxidants and EDTA treatment was studied when sea mussel was pressed and hot-air dehydrated for 10 hours at 45 to $52^{\circ}C$ under the air flow rate of 3 meter per second. The results are as follows: 1) Cooked and pressed sea mussel was dehydrated mere rapidly than cooked without pressing. 2) The rehydration rate of pressed and dehydrated sea mussel was higher than that of the unpressed. 3) Among six samples, BHA treated material showed the best color preservation during dehydration and storage. The treatment of Teonox-II was also effective following BHA. 4) The effects of antioxidants used during dehydration and storage were in order of BHA, Tenox-II and NDGA treatment, while EDTA was ineffective. 5) No significant difference in rehydration rate was found between those treated with antioxidants or EDTA and the untreated. 6) The amount of soluble protein was higher in the samples treated with antioxidants than in EDTA treated or untreated samples. 7) The results suggest that the treatment of BHA and pressing process produce improved product in quality which gives higher amount of soluble protein and better rehydration, color preservation and preventive effect of rancidity.