• Title/Summary/Keyword: bio materials

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Physical Properties of UV-Curable Powder Coatings with Different Photoinitiator Contents (광개시제의 함량에 따른 UV 경화형 분체도료의 물리적 특성)

  • Moon, Je-Ik;Choi, Jae-Hoon;Hwang, Hyun-Deuk;Kim, Hyun-Joong;Kim, Nam-Hong
    • Journal of Adhesion and Interface
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    • v.9 no.2
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    • pp.32-37
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    • 2008
  • A series of UV-curable powder coatings with different contents of photoinitiator (0.5 wt%, 1 wt%, 2 wt%) were formulated and measured gel content, tensile strength of cured film. Heat-sensitive substrates such as MDF, plywood and PVC were coated UV-curable powder and cured coatings were measured physical properties by pendulum hardness tester, glossmeter, pull-off adhesion tester. With increasing photoinitiator content, adhesion force between coating and substrate decreased because of crosslinking density increasing. The results of pendulum hardness was not significantly changed but gloss was changed according to different substrates. Adhesion of UV-curable coatings was enough to apply for heat-sensitive substrates. From these results, we concluded that contents of photoinitiator was a effective factor in UV-curable powder coatings. UV-curable coatings was a portential candidate for heat-sensitive substrates.

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A Parametric Study on Ethanol Production from Xylose by Pichia stipitis

  • Lee Tae-Young;Kim Myoung-Dong;Kim Kyu-Yong;Park Kyungmoon;Ryu Yeon-Woo;Seo Jin-Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.1
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    • pp.27-31
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    • 2000
  • Characteristics of ethanol production by a xylose-fermenting yeast, Pichia stipitis Y-7124, were studied. The sugar consumption rate and specific growth rate were higher in the glucose-containing medium than in the xylose-containing medium. Specific activities of xylose reductase and xylitol dehydrogenase were higher in the medium with xylose than glucose, suggesting their induction by xylose. Maximum specific growth rate and ethanol yield were achieved at 30 g xylose/L concentration without formation of by-products such as xylitol and acetic acid whereas a maximum ethanol concentration was obtained at 130 g/L xylose. Adding a respiratory inhibitor, rotenone, increased a maximum ethanol concentration by $10\%$ compared with the control experiment. In order to evaluate the pattern of ethanol inhibition on specific growth rate, a kinetic model based on Luong's equations was applied. The relationship between ethanol concentration and specific growth rate was hyperbolic for glucose and parabolic for xylose. A maximum ethanol concentration at which cells did not grow was 33.6 g/L for glucose and 44.7 g/L for xylose.

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Genomic Organization and Isoform-Dependent Expression Patterns of Wap65 genes in Various Tissues during Immune Challenges in the Mud Loach Misgurnus mizolepis

  • Kim, Yi Kyung;Cho, Young Sun;Lee, Sang Yoon;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • v.17 no.4
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    • pp.471-478
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    • 2014
  • Genomic organization, including the structural characteristics of 5'-flanking regions of two 65-kDa protein (WAP65) isoform genes associated with warm temperature acclimation, were characterized and their transcriptional responses to immune challenges were examined in the intestine, kidney and spleen of the mud loach (Misgurnus mizolepis; Cypriniformes). Both mud loach Wap65 isoform genes displayed a 10-exon structure that is common to most teleostean Wap65 genes. The two mud loach Wap65 isoforms were predicted to possess various stress- and immune-related transcription factor binding sites in their regulatory regions; however, the predicted motif profiles differed between the two isoforms, and the inflammation-related transcription factor binding motifs, such as NF-${\kappa}B$ and CREBP sites, were more highlighted in the Wap65-2 isoform than the Wap65-1 isoform. The results of qRT-PCR indicated that experimental immune challenges using Edwardsiella tarda, lipopolysaccharide or polyI:C induced the Wap65-2 isoform more than Wap65-1 isoform, although modulation patterns in response to these challenges were tissue- and stimulant-dependent. This study confirms that functional diversification between the two mud loach Wap65 isoforms (i.e., closer involvement of Wap65-2 in the acute phase of inflammation and innate immunity) occurs at the mRNA level in multiple tissues, and suggests that such differential modulation patterns between the two isoforms are related to the different transcription factor binding profiles in their regulatory regions.

Effects of far infrared radiological materials on immune response and changes of fecal microorganism in pigs (돼지에 있어 원적외선 방사물질의 첨가가 면역반응 및 분중 미생물의 변화에 미치는 영향)

  • Kwon, Ki-bum;Kim, In-ho;Hong, Jong-wook;Moon, Tea-hyun;Choi, Sang-yul;Seok, Ho-bong
    • Korean Journal of Veterinary Research
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    • v.41 no.1
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    • pp.37-42
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    • 2001
  • This research was conducted to investigate the effects of far infrared radiological materials on growth performance, immune response and changes of microbial flora in feces for growing pigs. Twelve growing pigs($Duroc{\times}Yorkshire{\times}Landrace$, average initial body weight of $15.6{\pm}0.5kg$) were used in a 40 day growth assay. Treatments were control(saline injection with diet: S); saline injection with Bio-Plus in diet(SBP); and vaccination with Bio-Plus in diet(VBP) in a randomized complete block design with initial BW as the blocking criterion. Serum concentrations of IgG of SBP and VBP were higher than those of S at day 10(p<0.05), 20(p<0.05), 30(p<0.05) and 40(p<0.05). Pigs fed with treatment diets had increased lymphocyte level compared to S at day 20(p<0.05) and 40(p<0.05). Cortisol was lower in treatments than in S at day 30(p<0.05). At day 20, there was no significant difference in E. coli among the treatments. However, it was observed that E, coli of the treatments was decreased compared to S at day 40(p<0.01). Lactobacillus of SBP was significantly higher(p<0.05) than that of S at day 40. In conclusion, the results of the experiment suggest that far infrared radiological materials could be a very beneficial immune response for growing pigs in health aspects.

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Acoustic Characterization of Coatings for Stringed Instruments with Various Coating Thickness (도막두께에 따른 현악기용 도료의 음향적 성질)

  • Choi, Jae-Hoon;Hwang, Heon-Deuk;Lee, Byoung-Hoo;Kim, Hyun-Joong;Chung, Woo-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.1
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    • pp.32-39
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    • 2006
  • The acoustic properties of various coatings for stringed musical instruments made were investigated. The applied coatings were urethane topcoat, oil stain and UV-curable epoxy coating. Acoustic properties of coatings inferred from the elastic modulus and the shear modulus that ware calculated from a resonance frequency and a damping measured by FFT analyzer. The relationship between elastic modulus and density and the relationship between elastic modulus and shear modulus of coatings for stringed musical instruments ware investigated as a function of coating thickness.

Analysis of Power Shuttle Characteristics of Agricultural Tractor (농업용 트랙터의 전후진 파워시프트 변속 특성 해석)

  • 김대철;이호상;정병학;김경욱
    • Journal of Biosystems Engineering
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    • v.27 no.6
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    • pp.479-490
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    • 2002
  • A dynamic model of a power shuttle transmission was developed and its validity was verified using the experimental data obtained from a transmission test bench. A 40㎾, 4WD tractor was also modeled using an application software EASY5 to investigate parameters and their effects on the power shifting performance. For a tractor model, the manual reverse gear was replaced by a power shuttle transmission. The tractor model also included an engine, main-gears for transmission, wheels, differentials and planet gears. Using the tractor model, the effects of the parameters such as modulating pressure and time, engine speed, tractor speed. tractor weight. reverse to forward speed ratio and torsional damper on the transient characteristics at starting and shuttle shifting were investigated by the computer simulation. The transient characteristics were represented by variations in clutch pressure, torque transmitted to input shaft and driving wheels, and power transmission capacity of the clutch. It was found that the modulating pressure and time affected most significantly the torque transmission and shifting time. The input torque, axle torque, power transmission capacity of the clutch and transmission time all increased with increase in engine speed, tractor speed. tractor weight and ratio of reverse to forward speeds. However, the axle torque decreased with tractor speed. Both the axle torque and power transmission capacity of the clutch also decreased with the ratio of reverse to forward speeds.

Anti-inflammatory Effect of Fallopia sachalinensis RonseDecr. Fruit (왕호장 열매의 항염증 효과)

  • Park, Sung Ha;Jeong, Jeong Hyeon;Park, Byoung Jun;Jeong, Tae Hwa
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.3
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    • pp.237-241
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    • 2015
  • To develop a new anti-inflammation agent for cosmetics, we investigated the anti-inflammatory activity of Fallopia sachalinensis RonseDecr. fruit extracts (FSR). FSR inhibited the pre-inflammatory cytokines ($1L-1{\beta}$, IL-6, TNF-${\alpha}$) and reduced NO production of RAW 264.7 macrophage cells in a dose-dependent manner and decreased the activity to about 51% at a concentration of $100{\mu}g/mL$. FSR suppressed not only the mRNA expression of iNOS and COX-2, but also the protein expression of iNOS and COX-2 in macrophage. The results suggested that FSR has considerable potential as a cosmetics ingredient with an anti-inflammatory effect.

Whitening Effect of Biochanin A (Biochanin A의 미백 효과에 관한 연구)

  • Park, Sung Ha;Kim, A Hyun;Park, Byoung Jun;Kim, Jin Jun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.4
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    • pp.289-294
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    • 2013
  • To develop a new whitening agent for cosmetics, we investigated the inhibitory effects of biochanin A on melanogenesis. The biochanoin A is an active component in the extracts of Dalbergia odorifera T. Chen. It reduced melanin contents of B16F1 melanoma cells in a dose-dependent manner and decreased to about 48% at a concentration 10 ${\mu}g/mL$. It also inhibited the expression in microphthalmia associated transcription factor (MITF), Tyrosinase, Tyrosinase related protein 1 (Trp-1), and Tyrosinase related protein 2 (Trp-2) in melanocytes. The results suggested that biochanin A has considerable potential as a cosmetics ingredient with a whitening effect.

Abatement of Metal Ion Contents from Cotton Linter for the Manufacture of Regenerated Cellulose (방직용 재생섬유 제조를 위한 면 린터의 금속이온 함량 저감에 관한 연구)

  • Park, Hee Jeong;Son, Ha Neul;Choi, Jin Sung;Seo, Yung Bum
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.6
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    • pp.17-23
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    • 2013
  • The reduction of metal ion from the cotton linter for the preparation of NMMO (N-methylmorpholine N-oxide)-based dissolving pulp was investigated. The NMMO-based dissolving pulp was usually used for the manufacture of high quality fabrics, and need to have high alpha cellulose content and high brightness. NMMO, which is environmentally friendly, and reusable after recovering process, is very sensitive to the metal ions such as Cu, Fe, Mg, and Cr. Electron beam, sulfuric acid, acetic acid, and ozone treatment before bleaching were used and the concentration changes of the metal ions were compared to that of EDTA, a chelating agent. It was found that both acid treatments (sulfuric and acetic acid) were very effective and comparable to EDTA treatment at the same dosage in metal ion reduction, but electron beam and ozone treatment were not. The sulfuric acid treatment turned out to be effective in metal ion reduction, and most inexpensive.

Dispersing Properties of Heavy Crude Oil according to Dispersant Structures (중유용 분산제 구조에 따른 중유 분산 특성)

  • Son, Jeong-Mae;Kim, Nam-Kyun;Shin, Jihoon;Yang, Youngdo;Kim, Young-Wun
    • Tribology and Lubricants
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    • v.31 no.6
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    • pp.251-257
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    • 2015
  • Heavy oil production is receiving significant attention because of increased demands for thermal power generation systems of the diesel engine and boilers. However, asphaltene, which is a heavy oil components (6-8 wt%), reduces the heat efficiency of the fuels owing to its agglomerated sludge of asphaltene during the burning process. Therefore, for hassle-free operation, we should develop asphaltene dispersants to suppress the formation of the sludge. We prepare variable salt-type polymeric dispersants using poly(isobutenyl succinic anhydride) and poly(amine) through both condensation esterification and acid-base neutralization reactions, which we subsequently evaluate for dispersing performance, using Turbiscan measurement. Total acid number (TAN) and total base number (TBN) of 75Lec-25SynDis.2 composed of lecithin and the prepared polymeric salt having the ratio of 3 : 1 are 18.9 and 33.7 mg KOH/g, respectively, which are comparable to those of the commercial dispersants (15.8 and 26.5 mg KOH/g). We determine the initial turbidity observed for 15 min of the polymeric dispersant was determined with transmittance (%), which can be calculated to separability number (SN). The SN value of 75Lec-25SynDis.2 is close to zero, which is superior to that of commercial dispersants and lecithin (0.015 and 0.017).