• 제목/요약/키워드: Fibrous

검색결과 1,516건 처리시간 0.026초

하이드록실 아민으로 처리한 아크릴섬유의 구리 (II)이온의 흡착기구 (The Adsorption Mechanism of Copper (II) Ion on Acrylic Fiber Treated with Hydroxylamine)

  • 진영길;최석철
    • 한국의류학회지
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    • 제12권1호
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    • pp.27-35
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    • 1988
  • In order to investigate a practical application of the fibrous adsorbent to heavy metal ions, acrylic fibers were treated with the hydroxylamine solution that was producted by hydroxylamine hydrochloride and potasium hydroxide in a condition of strong alkaline and $70^{\circ}C$. The adsorption mechanism of copper(2) ion on the fibrous adsorbent, that is hydroxylaminated acrylic fibers, was studied. The adsorption of copper(2) ion was explained in terms of the activated adsorption that are formed the complex with the ligand, such as C=N, N-H, NHOH, on the surface of the adsorbent. The activation energy was evaluated to be 3.8 Kcal/mol. and the times of adsorption equilibrium was approximately 10 minutes. The uptake of copper(2) ion was found to be effected with the increase of temperatures and the pH dependence.

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다꾸치법에 의한 무섬유 세라믹 브레이크 마찰재의 제조변수에 대한 고찰 (Investigation of Manufacturing Parameters for Non-fibrous Ceramic Brake Pads using Taguchi Method)

  • 여정구;최성철
    • 한국재료학회지
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    • 제14권1호
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    • pp.59-66
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    • 2004
  • In the present study, ceramic brake pads without fiber phases were manufactured by the low temperature heat treatment below$ 700 ^{\circ}C$. The manufacturing parameters of ceramic brake pads and those levels were investigated by the analysis results of signal-to-noise ratios, ANOVA based upon the Taguchi method. The ceramic brake pads prepared in the Mg experiment had a friction coefficient of 0.30~0.55 very close to the target coefficient (0.35~0.45) of commercial brake pads utilized in the automobiles. The frictional properties of ceramic brake pads could be stabilized with the adjustment of amounts of lubricating additives. The optimum preparation conditions as well as batch formulations for the fabrication of non-fibrous ceramic brake pads were finally determined using Taguchi method in this study.

금붕어(Carassius auratus L.) 피부(皮膚) 색소세포(色素細胞)의 미세구조(微細構造) 및 色素顆粒(색소과립) 형성(形成)에 관한 연구(硏究) I. 황색소세포(黃色素細胞)(xanthophore) (Ultrastructures of the Cutaneous Chromatophores and Pigment Granule Formation in the Goldfish, Carassius auratus L. I. Xanthophore)

  • 문명진;김우갑;김창환
    • Applied Microscopy
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    • 제16권2호
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    • pp.35-48
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    • 1986
  • Ultrastructures of the cutaneous xanthophores and formation of pigment granules in the goldfish, Carassius auratus L., are studied with electron microscope. The cutaneous xanthophores are observed only in dermis and pigment granules of these pigment cells are pterinosomes and carotenoid vesicles. By the differentiated level, pterinosomes are subdivided into 3 types; while type I pterinosomes have clear limiting membranes and contain some amorphous fine fibrous structures, type II pterinosomes have thick and densely aggregated fibrous materials. Type III pterinosomes have concentric lamellar structures in the granules. Pigment granules of the xanthophores are originated from the Golgi complexes and pinocytotic vesicles of plasma membrane as well as rER-rich cells among the chromatophores are presumed to be associated with the accumulation of pigment materials.

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Dissolution Technology Development of E-Glass Fiber for Recycling Waste of Glass Fiber Reinforced Polymer

  • Lee, Suyeon;Kim, Woo Sik
    • 한국세라믹학회지
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    • 제56권6호
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    • pp.577-582
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    • 2019
  • Recently, E-glass fiber is the one of most widely used ceramic fiber for aerospace fields. Recycling technology for waste of wind power blades is arising issue for reasons of low manageability and high cost of wastes. Though glass fiber is perfectly dissolved in hydrofluoric acid, low cost for recycling and harmless to human is important for recycling of blades. Chemically melted glass fiber will be used as different purpose like accelerator of hardening for shotcrete. In this study, dissolution process of glass fiber is tested in NaOH solution at low temperatures. In addition, difference in diameter reduction of glass fiber is observed by various alkali concentration and reaction times, treatment temperatures using FE-SEM.

구강내 발생한 지방종 2례 (Two Cases of Lipoma of the Oral Cavity)

  • 권기환;이상혁;진성민;이용배
    • 대한두경부종양학회지
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    • 제16권1호
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    • pp.80-82
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    • 2000
  • Lipoma is a benign neoplasm composed of mature fat cells and usually circumscribed by a fibrous capsule. The fat cells are arranged in irregular lobules, partitioned by fibrous septa with supportive vascular channels. Lipoma of the oral cavity is uncommon, and has been reported to be infrequent in the literature in the world so far. An oral lipoma mainly occurs in the cheek and tongue. Surgical excision is the only treatment recommended, and prognosis is uniformly excellent. Recently we experienced two cases of lipoma of the oral cavity and removed the tumor completely by surgical excision.

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규산질미분말혼합시멘트계도포방수재료가 습윤환경하의 콘크리트의 미세조직에 미치는 영향 (Effect of Siliceous Slury Coating on Microstructure of Concrete under Damp Environment)

  • 오상근
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1992년도 가을 학술발표회 논문집
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    • pp.1-4
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    • 1992
  • This paper deals with the effect of siliceous slurry coating on concrete microstructure under damp environment. This material is mixed inorganic powder consisted of silica, cement and fine sand and water. Water pressure was given on the coated surface of concrete. for estimation on effect of siliceous slurry coating, microstructure of coated concrete was observed through SEM, and chemical components of crystals were analyzed with X-ray diffraction and EDX. A number of needle and fibrous crystals were produced in microstructure. And based on X-ray diffraction and EDX, needle crystal mainly consist of Al, Si, and Ca, and it is concluded to be ettringite. Fibrous crystals consist of Ca and Si, and it to be calcium silicate hydrate.

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애완 이구아나의 피하에 발생한 건락괴사성 종류 (Subcutaneous Caseous Necrotic Mass in a Pet Iguana (Iguana iguana))

  • 조경오;박남용;강성귀;김용환;김계엽;이근우
    • 한국임상수의학회지
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    • 제18권1호
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    • pp.88-92
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    • 2001
  • A subcutaneous mass foud in a nine-year-old male Iguana (Iguana iguana) was pathologically and microbiologically examined. Grossly, this mass, measuring $2 cm{\times}1.5 cm{\times}1 cm$ in size, contained white to yellow caseous-crumbly material which was surrounded by the thin connective tissue. Histopathologically, a mass consisted of central caseous necrotic debri in which heterophils and macrophages were scattered, and peripheral fibrous connective tissue in which scattered heterophils, macrophages and lymphoid cell aggregates were present. This mass composed of central necrotic core and peripheal connective tissue did not have any detectable microorganisms including acid-fast bacteria and fungi. Histopathologically, severe atrophy of seminiferous tubules in both testicles was observed. In addition, peripheri of ductus deferens was thickened by fibrous connective tissue. This is the first report of subcutaneous caseous necrotic mass of an Iguana in Korea. In addition, the bilateral severe atrophy of seminiferous tubules may be due to fibrosis of ductus deferens.

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휨거동을 만족하는 강섬유보강 철근콘크리트보의 최적화 (Optimization of Reinforced Steel Fibrous Concrete Beam for the Objective Flexural Behavior)

  • 이차돈;안지현
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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    • pp.541-546
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    • 1998
  • The use of steel fibers in conventional reinforced concrete increases the strength and ductility under various loading conditions. In order to examine the possibility of the use of these combinations achieving required strength and ductility of a reinforced concrete beam, a refined optimization procedure based on nonlinear layered finite element method and nonlinear programming technique is developed in this study. Six design variables-beam width and depth, fiber volume fraction, amounts of tensile and compressive rebars, and stirrup, and stirrup spacing-are considered. The developed model can be used as a tool in determining the economical use of steel fibers in designing the reinforced steel fibrous concrete beam.

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