• Title/Summary/Keyword: Conjugate fiber

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Effect of Torch Speed and Solid Layer Thickness on Heat Transfer and Particle Deposition During modified Chemical Vapor Deposition Process (수정된 화학증착과정에서 토치이송과 고체층이 열전달과 입자부착에 미치는 영향)

  • 박경순;최만수
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.5
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    • pp.1301-1309
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    • 1994
  • A study of heat transfer and thermophoretic particle deposition has been carried out for the Modified Chemical Vapor Deposition(MCVD) process. A new concept utilizing two torches is suggested to simulate the heating effects from repeated traversing torches. Calculation results for the wall temperatures and deposition efficiency are in good agreement with experimental data. The effects of variable properties are included and heat flux boundary condition is used to simulate the moving torch heating. A conjugate heat transfer which includes heat conduction through solid layer and heat teansfer in a gas in a tube is analyzed. Of particular interests are the effects of torch speeds and solid layer thicknesses on the deposition efficiency, rate and the tapered entry length.

Preparation and Characterization of Low Infrared Emissivity Bicomponent Fibers with Radar Absorbing Property (레이더 흡수특성이 있는 저적외선 방출 복합섬유의 제조 및 특성 연구)

  • Yu Bin;Qi Lu
    • Polymer(Korea)
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    • v.30 no.2
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    • pp.124-128
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    • 2006
  • Heavy weight of the camouflage materials was always the main problem. To solve it, the low infrared emissivity fibers with the radar absorbing property (LIFR) were prepared. The low infrared emissivity fibers (LIF) were firstly melt-spun by co-extrusion of polypropylene (PP) and PP/various fillers master-batches using general conjugate spinning. The infrared emissivity of LW with AA and ZnO was decreased respectively compared with that of pure polypropylene fibers. The infrared emissivity of LIF with 15 wt% Al and 2 wt% ZnO in the sheath-part can reach 0.58. To improve LIF radar absorbing property, LIFR was prepared by filling the 50 wt% ferrite and bronze in the core-part of LIF. The radar absorbing efficacy of LIFR was good and the infrared emissivity was low. For the characterization, fiber electron intensity instrument and differential scanning calorimetry (DSC) were used for the analysis of mechanical properties, thermal and crystallization behavior of the spun-fibers. Scanning electron microscopy (SEM) was carried out to observe the particle distribution of the bicomponent fibers.

An Enzyme-linked Immunosorbent Assay Strip Sensor for the Detection of Legionella Pneumophila (Legionella Pneumophila 검출을 위한 효소면역측정 스트립 센서)

  • Kim, Young-Kee;Park, Sojung
    • Applied Chemistry for Engineering
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    • v.25 no.5
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    • pp.544-547
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    • 2014
  • In this study, an enzyme-linked immunosorbent assay (ELISA) and immuno-chromatographic technique were combined to fabricate immuno-strip sensors for the detection of Legionella pneumophila. The immuno-strip sensor was manufactured with four different membranes. A nitrocellulose membrane was used to immobilize capture antibody and generate signals due to the high affinity to antibodies, and glass fiber membranes were used as a conjugate release pad and a sample application pad. A cellulose membrane was used as an absorption pad to induce sample flow by the capillarity. Colorimetric signals produced by sandwich immuno-reaction and enzyme reaction could be analyzed qualitatively and quantitatively within 30 min. Under the given experimental conditions, sensor signals with L. pneumophila samples were observed qualitatively by naked eyes and measured quantitatively in a range of $1.3{\times}10^3-1.3{\times}10^6CFU/mL$ with a digital camera and home-made image analysis software.

Dietary beet pulp decreases taurine status in dogs fed low protein diet

  • Ko, Kwang Suk;Fascetti, Andrea J.
    • Journal of Animal Science and Technology
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    • v.58 no.8
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    • pp.29.1-29.10
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    • 2016
  • Background: It is known that large dogs who are fed lamb and rice diets are at increased risk to develop taurine-deficiency-induced dilated cardiomyopathy. Since dogs obligatorily conjugate bile acids (BA) with taurine, we determined whether rice bran (RB) or other fibers (cellulose; CL, beet pulp; BP) would affect BA excretion and/or the taurine status of dogs. Results: Eighteen medium/large mixed-breed dogs were given purified diets containing CL, BP, or RB for 12 weeks. Taurine concentrations in plasma and whole blood were significantly decreased at week 12. The BP group, compared to the CL or RB groups, showed significantly lower taurine concentrations in plasma ($6.5{\pm}0.5$ vs $20.4{\pm}3.9$ and $13.1{\pm}2.0{\mu}mol/L$, respectively, P < 0.01, $mean{\pm}SEM$) and in whole blood ($79{\pm}10$ vs $143{\pm}14$ and $127{\pm}14{\mu}mol/L$, respectively, P < 0.01), lower apparent protein digestibility ($81.9{\pm}0.6$ vs $88.8{\pm}0.6$ and $88.1{\pm}1.2%$, respectively, P < 0.01), and higher BA excretions ($5.6{\pm}0.1$ vs $3.4{\pm}0.5$ and $3.4{\pm}0.4{\mu}mol/g$ feces, respectively, P < 0.05) at week 12. Conclusions: These results do not support the hypothesis that RB is likely to be a primary cause of lamb meal and rice diets, increasing the risk of taurine deficiency in large dogs. However these indicate that BP may contribute to a decrease taurine status in dogs by increasing excretion of fecal BA and decreasing protein digestibility, thus decreasing the bioavailability of sulfur amino acids, the precursors of taurine.

A STUDY ON THE DISTRIBUTION OF CALCITONIN GENE-RELATED PEPTIDE CONTAINING NERVE FIBERS IN RAT PULP FOLLOWING DENTINAL INJURY (상아질 손상 후 흰쥐 대구치 치수의 calcitonin gene-related peptide(CGRP) 함유 신경섬유 분포에 관한 연구)

  • Moon, Joo-Hoon;Park, Sang-Jin;Min, Byung-Soon;Choi, Ho-Young;Cho, Gi-Woon
    • Restorative Dentistry and Endodontics
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    • v.24 no.1
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    • pp.100-115
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    • 1999
  • The purpose of this study was to investigate the distribution of calcitonin gene-related peptide containing nerve fibers in rat pulp after dentinl injury by means of immunohistochemistry and confocal laser scanning microscope. The Spague-Dawley rats weighing about 250-300gm were used. The animals were devided into normal control and experimental groups. Experimental animals were sacrified 1, 2, 4, 7, 10, 21days after dentinal injury (dentin cutting, and then acid etching with 35% phosphoric acid) on the maxillary molar teeth. The maxillary teeth and alveolar bone were removed and immersed in the 4% paraformaldehyde in 0.1M phosphate buffer (pH 7.4), then were decalcified with 15% formic acid for 10 days. Serial frozen $50{\mu}m$ thick sections were cut on a cryostat. The rabbit CGRP antibody was used as a primary antibody with a dilution of 1:2000 in 0.01M PB. The sections were incubated for 48 hours at $4^{\circ}C$, and placed into biotinylated antirabbit Ig G as a secondary anti body with dilution of 1:200 in 0.01M PB and incubated in ABC(avidin-biotin complex). The peroxidase reaction was visualized by incubating the sections in 0.05% 3,3 diaminobenzidine tetrahydrochloride containing 0.02% $H_2O_2$. For the confocal laser scanning microscopic examination, Primary antibody reaction was same as immunoperoxidase stainning, but fluorescein isothiocyanate(FITC)-conjugate antirabbit IgG as a secondary antibody was used. The confocal laser scanning microscope was used for the examination. A series of images of optical sections was collected with a 20x objective at $3{\mu}m$ intervals throughout the depth of specimen. FITC fluerescence was registrated through a 488nm and 568nm excitation filter, and images were saved on optical disk. The stereoscopic images and three dimentionnal images were reconstructed by computer software, and then were analyzed. The results were as follows : 1. In normal control group, CGRP containing nerve fibers were coursed through the root with very little branching, and then formed a dense network of terminals in coronal pulp. 2. A slight increase in CGRP containing nerve fibers at 1 and 2day postinjury was noted subjacent to the injury site. In the 4day group, there were an extensive increase in the number of reactive fibers, followed by a partial return toward normal levels at 7~10 day postinjury, and return by 21days. 3. The sprouting of the CGRP containing nerve fibers was evident within 2day after dentinal injury, and by 4days there was a maximal increased, but was decreased at 7days and returned to normal 10~21 day postinjury. 4. In confocal laser scanning microscopic exammination, the distinct distribution pattern and sprouting reaction of CGRP containing nerve fibers were observed in stereoscopic images and three dimentional images. These results suggest that CGRP containing nerve fiber can be important role in the response to dental injury and pain regulation.

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