• 제목/요약/키워드: Conjugate fiber

검색결과 15건 처리시간 0.017초

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

  • 박경순;최만수
    • 대한기계학회논문집
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    • 제18권5호
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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.

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

  • Yu Bin;Qi Lu
    • 폴리머
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    • 제30권2호
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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.

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

  • 김영기;박소정
    • 공업화학
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    • 제25권5호
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    • pp.544-547
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    • 2014
  • 본 연구에서는 효소면역 분석법(enzyme-linked immunosorbent assay)과 면역크로마토그래픽 기법을 결합하여 Legionella pneumophila 검출을 위한 면역스트립을 제작하였다. 면역스트립은 4종의 멤브레인을 이용하여 제작하였다. 니트로셀룰로오스 멤브레인은 포획항체를 고정화하여 신호 발생을 일으키기 위해 사용되었고, 두 종류의 유리섬유 멤브레인은 각각 중합체 패드와 시료주입 패드로 사용되었다. 셀룰로오스 멤브레인은 모세관 현상으로 시료흐름을 유도하는 흡수 패드로 이용하였다. 샌드위치 면역반응과 효소반응에 의해 30 min 이내에 생성된 발색신호는 정성 및 정량 분석이 가능하였다. 분석조건 하에서 육안에 의한 정성 검출뿐 아니라, $1.3{\times}10^3-1.3{\times}10^6CFU/mL$ 범위의 L. pneumophila 농도를 디지털카메라와 자체 제작된 소프트웨어를 이용하여 정량적으로 분석할 수 있었다.

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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    • 제58권8호
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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.

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

  • 문주훈;박상진;민병순;최호영;최기운
    • Restorative Dentistry and Endodontics
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    • 제24권1호
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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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