• Title/Summary/Keyword: fiberglass

검색결과 131건 처리시간 0.025초

The effect of individualization of fiberglass posts using bulk-fill resin-based composites on cementation: an in vitro study

  • Lins, Rodrigo Barros Esteves;Cordeiro, Jairo Matozinho;Rangel, Carolina Perez;Antunes, Thiago Bessa Marconato;Martins, Luis Roberto Marcondes
    • Restorative Dentistry and Endodontics
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    • 제44권4호
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    • pp.37.1-37.10
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    • 2019
  • Objectives: This study evaluated the bond strength of various fiberglass post cementation techniques using different resin-based composites. Materials and Methods: The roots from a total of 100 bovine incisors were randomly assigned to 5 treatment groups: G1, post + Scotchbond Multi-Purpose (SBMP) + RelyX ARC luting agent; G2, relined post (Filtek Z250) + SBMP + RelyX ARC; G3, individualized post (Filtek Z250) + SBMP; G4, individualized post (Filtek Bulk-Fill) + SBMP; G5, individualized post (Filtek Bulk-Fill Flow) + SBMP. The samples were subjected to the push-out (n = 10) and pull-out (n = 10) bond strength tests. Data from the push-out bond strength test were analyzed using 2-way analysis of variance (ANOVA) with the Bonferroni post hoc test, and data from the pull-out bond strength test were analyzed using 1-way ANOVA. Results: The data for push-out bond strength presented higher values for G2 and G5, mainly in the cervical and middle thirds, and the data from the apical third showed a lower mean push-out bond strength in all groups. No significant difference was noted for pull-out bond strength among all groups. The most frequent failure modes observed were adhesive failure between dentine and resin and mixed failure. Conclusions: Fiberglass post cementation using restorative and flowable bulk-fill composites with the individualization technique may be a promising alternative to existing methods of post cementation.

토양 간극수의 효율적 포집을 위한 오염물질 제거에 관한 연구 (A Study of Contaminant Removal for Pore-Water Collection)

  • 이성백
    • 한국토양환경학회지
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    • 제4권1호
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    • pp.69-73
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    • 1999
  • PCAPS는 토양 간극수를 효율적으로 포집하기 위해서 fiberglass wick의 모세관 잠재력을 이용하여 토양오염을 조사하는 장치이다. Fiberglass에 붙어 있는 불순물은 wick의 모세관 성질과 포집된 시료의 화학적 성질에 영향을 미치게 되므로 4가지 처리방법들 (소각처리, 아세톤처리, 세정제처리, 비세척)을 이용하여 불순물을 제거하였다. Wick은 미국의 PPG Industries와 Manville Company에서 생산되는 제품을 사용하였다. 실험결과로, PPG fiber는 소각처리에 의해 원래 부피의 3.4%정도 손실되었으며, Manville fiber 는 0.6%미만이 손실되었다. 이들 손실은 제작과정에 사용된 유기합성물이 소각되면서 발생하였다. 모든 세척방법들은 비세척 방법보다 모세관의 상승높이가 더 크게 나타났다. 소각이 가장 좋은 세척방법으로 나타났으며 40$0^{\circ}C$의 온도에서 4시간 처리시 불순물의 98~100%를 제거할 수 있었다.

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Successful Carapace Puncture Wound Repair with Polymethyl Methacrylate (PMMA) in an Amur Softshell Turtle (Pelodiscus maackii)

  • Ha, Minjong;Lee, Do Na;Ahmed, Sohail;Han, Janghee;Yeon, Seong-Chan
    • 한국임상수의학회지
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    • 제39권4호
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    • pp.185-191
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    • 2022
  • An Amur softshell turtle with multiple shell injuries was admitted to the Seoul Wildlife Center on 19 May 2021. The most severe lesion was a puncture wound requiring urgent closure. In addition to routine supportive therapy, the damaged shell was patched with biocompatible polymethyl methacrylate (PMMA) materials (bone cement and dental acrylic) and fiberglass. Despite a few methods to repair the carapace or plastron of hard-shelled turtles, shell repair in the Amur softshell turtle has rarely been reported. This paper reports the repair process of a puncture wound in the carapace of a softshell turtle using polymethyl methacrylate (PMMA). PMMA is a biocompatible acrylic polymer that forms a tight structure that holds the implant against tissue defects, such as skin, bones, and dentures. Fiberglass, a preferred fiber in various medical fields, was used with PMMA to provide extra strength and waterproof capability. After the procedure, there were no signs of edema, inflammation, bleeding, skin discoloration, or any other complications. Accordingly, this can be a method of choice in softshell turtles using biocompatible materials to cover the lesion in the carapace and provide appropriate wound management, supportive therapy, and a suitable course of antibiotics considering all other circumstances.

레저용 쌍동선 선박 설계와 제작(IV)

  • 선박검
    • 선박안전
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    • 제15권
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    • pp.45-53
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    • 2004
  • 세계적으로 레저선박에서 가장 일반적인 선체의 재질은 아직까지 Fiberglass Reinforcement Plastic이다. 선체의 재질이 아직까지 FRP에서 알루미늄으로 변화하지 못하는 이유는 중, 소형 선박을 다량으로 제조할 때 FRP는 가장 효율적인 작업이 가능하고 경제성이 뛰어나며 선체의 외관에 제약이 크게 없는 재료이기 때문이다.<중략>

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해양온도차 발전을 위한 심층수 파이프 직경에 따른 에너지 손실량 검토 (Feasibility Study on Cold Water Pipe Diameter by Friction Loss and Energy Conversion on OTEC)

  • 정훈;허균영
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 추계학술대회 초록집
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    • pp.170-170
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    • 2010
  • The energy conversion from the temperature difference between hot and cold source like ocean thermal energy conversion (OTEC), requires a long and large-diameter pipe (about 1000 to 10,000 meters long) to reach the deep water. The pipe diameter ranges from 2.8 meter for proposed early test systems, to 5 meter for large, commercial power generation systems. The pipe must be designed to resist collapsing pressures produced by water temperature and density differences, and the reduced pressure required to induce flow up the pipe. Other design considerations include the external-drag effect on the pipe due to ocean currents, and the wave-induced motions of the platform to which the pipe is attached. Various approaches to the pipe construction have been proposed, including aluminum, steel, concrete, and fiberglass. More recently, a flexible pipe construction involving the use of fiberglass reinforced plastic has been proposed. This report presents the results of a scaled fixed cold water pipe (CWP) model test program performed by EES(Engineering Equation Solver) to demonstrate the feasibility of this pipe approach.

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Structural performance of ferrocement beams reinforced with composite materials

  • Shaheen, Yousry B.I.;Eltaly, Boshra A.;Abdul-Fataha, Samer G.
    • Structural Engineering and Mechanics
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    • 제50권6호
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    • pp.817-834
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    • 2014
  • An experimental program was designed in the current work to examine the structural behavior of ferrocement beams reinforced with composite materials under three point loadings up to failure. The experimental program comprised casting and testing of twelve ferrocement beams having the dimensions of 120 mm width, 200 mm depth and 1600 mm length. The twelve beams were different in the type of reinforcements; steel bars, traditional wire meshes (welded and expanded wire meshes) and composite materials (fiberglass wire meshes and polypropylene wire meshes). The flexural performances of the all tested beams in terms of strength, ductility, cracking behavior and energy absorption were investigated. Also all the tested beams were simulated using ANSYS program. The results of the experimental tests concluded that the beam with fiber glass meshes gives the lowest first crack load and ultimate load. The ferrocement beam reinforced with four layers of welded wire meshes has better structural behavior than those beams reinforced with other types of wire meshes. Also the beams reinforced with metal wire meshes give smaller cracks width in comparing with those reinforced with non-metal wire meshes. Also the Finite Element (FE) simulations gave good results comparing with the experimental results.

터널보강재로서 FRP재료의 적용성 검토 (The applicability of FRP material for tunnel support)

  • 최용기;권오엽;배규진;조만섭
    • 한국터널지하공간학회 논문집
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    • 제3권1호
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    • pp.11-19
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    • 2001
  • 이 연구는 강관 보강형 다단 그라우팅공법의 설치 및 절단 시 어려움, 부식에 취약한 문제점 등을 개선하는데 목적이 있으며, 강관 대신에 고강도 유리섬유(fiberglass)를 이용한 FRP(Fiberglass Reinforced Plastic)의 적용성에 대한 연구를 수행하였다. 연구결과는 강관에 비하여 FRP 보강재의 가격이 높긴 하지만 시공성 및 내구성 등에서 우수한 것으로 파악되었다. 그리고 FRP 보강재의 형상에 따른 수치해석 결과에서는 국외에서 상용화 된 판상형 보강재 보다 등각곡선형 보강재가 더 구조적 측면에서 효율적임을 알 수 있었고, 그라우트 복합체에 대한 굴곡강도시험 결과에서는 강관과 FRP 보강재의 지보효과가 유사한 것으로 평가되었다.

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잠수함용 GFRP 표면결함 수리에 따른 기계적 특성변화 연구 (A Study on the Mechanical Characteristic Change Accordance with Surface Damaged Submarine GFRP Repairing)

  • 정영인;구자길;이윤석
    • 품질경영학회지
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    • 제48권2호
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    • pp.257-267
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    • 2020
  • Purpose: The purpose of this study is to define guideline for fiber-glass-resin-putty repairing method for submarine GFRP by comparing structural strength between normal GFRP and putty repaired GFRP. Methods: GFRP specimen tensile and flexural tests are conducted in accordance with ASTM D3039/3039M-17 and ASTM D790 Procedure A. The collected data was analysed whether satisfies its structural strength criteria. Furthermore, It is analysed to find dominant reason of structural strength changes. Results: The result of the study is as follows; flexural strength of GFRP is satisfied strength criteria for all test cases, but tensile strength is not satisfied its criteria for some cases which over 2 mm depth of surface damage. Conclusion: The fiberglass-resin-putty repairing method should be applied to under 2 mm depth of damage which is not affecting to roving fiber layer destruction in GREP laminate.

원사가 다른 건축용 막재의 인장 특성 연구 (Study for Tensile Properties of Architectural Membrane with different Yarn)

  • 서삼열;장명호;박강근;김승덕
    • 한국공간구조학회논문집
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    • 제10권3호
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    • pp.41-48
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    • 2010
  • 건축용 막재는 일반적으로 직포와 코팅으로 구성되며, PTFE 계열 막재는 유리섬유로 만들어진 직포에 테프론 코팅으로 구성된다. 일반적으로 PTFE 막재에 사용되는 직포에는 $\beta$-yarn이 주로 사용되며, $\beta$-yarn이 아닌 $\alpha$-yarn이 사용된 막재도 점차적으로 사용되는 시점이다. 그러나 $\alpha$-yarn으로 직조된 직포로 만들어진 건축용 막재의 특성에 관한 정보는 일반 막재에 비해 많이 부족한 편이다. 따라서 건축용 막재를 구성하는 직포를 만드는 원사의 굵기에 따른 막재의 역학적 특성에 대한 연구가 필요하다. 본 연구에서는 실험을 통하여 원사가 서로 다른 막재의 인장 특성을 비교 분석하고자 한다.

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