• 제목/요약/키워드: Powder characteristic

검색결과 425건 처리시간 0.023초

콘크리트의 유동성 개선을 위한 순환골재 활용에 관한 연구 (A Study on Application of Recycled Aggregate for Improving Fluidity of Concrete)

  • 송일현;류재석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.219-220
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    • 2009
  • 본 연구는 순환잔골재가 갖는 미분말이 자기충전 콘크리트(SCC)특성인 고강도와 높은 유동성을 발현하기에 적당하여 폐콘크리트에서 발생하는 순환잔골재를 천연잔골재 대비 혼입률을 25% 씩 증가시켜, 총 5수준으로 자기충전 콘크리트(SCC)에 적용하였으며, 이에 따라 굳지 않은 콘크리트의 물리적특성, 경화한 콘크리트의 역학적 및 내구특성을 검토하여 순환잔골재를 자기충전 콘크리트(SCC)로서의 활용 가능성을 검토하였다.

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AC-PDP에서 MgO 증착조건에 따른 패널특성 연구 (Effect of MgO Deposition Condition on the Discharge Characteristic of AC-PDP)

  • 정주영;조성용;이돈규;이해준;이호준;박정후
    • 전기학회논문지
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    • 제58권8호
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    • pp.1566-1571
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    • 2009
  • The discharge electrodes in ac PDP are coated with dielectric layer, and transparent MgO thin films are deposited on the dielectric layer. The main role of the MgO thin films in ac PDP is to protect the dielectric layer from sputtering by ion bombardment in the glow-discharge plasma. An additional important role of the MgO thin film is the high secondary electron emission coefficient which leads the low firing voltage and low cost of the PDP. In this paper, we investigated the relations of the crystal orientation about deposition thickness, deposition rate, temperature of substrate, and distance between the MgO tablet and the substrate. Additionally, we investigated the discharge characteristics of the AC PDP using nano-powder MgO tablet

Characteristic of size distribution of rock chip produced by rock cutting with a pick cutter

  • Jeong, Hoyoung;Jeon, Seokwon
    • Geomechanics and Engineering
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    • 제15권3호
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    • pp.811-822
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    • 2018
  • Chip size distribution can be used to evaluate the cutting efficiency and to characterize the cutting behavior of rock during cutting and fragmentation process. In this study, a series of linear cutting tests was performed to investigate the effect of cutting conditions (specifically cut spacing and penetration depth) on the production and size distribution of rock chips. Linyi sandstone from China was used in the linear cutting tests. After each run of linear cutting machine test, the rock chips were collected and their size distribution was analyzed using a sieving test and image processing. Image processing can rapidly and cost-effectively provide useful information of size distribution. Rosin-Rammer distribution pamameters, the coarseness index and the coefficients of uniformity and curvature were determined by image processing for different cutting conditions. The size of the rock chips was greatest at the optimum cut spacing, and the size distribution parameters were highly correlated with cutter forces and specific energy.

추진제 KM30Al의 저장 온도/습도와 저장수명과 관계 고찰 (A Study on the Effect of Storing Temperature and Humidity upon the Self Life of Propellant KM30Al)

  • 조기홍
    • 한국군사과학기술학회지
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    • 제9권1호
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    • pp.13-23
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    • 2006
  • A propellant mainly consisting of nitric ester including nitrocellulose and nitroglycerine is characteristic of being decomposed naturally. And this phenomenon is known as being affected mostly by its storing temperature and humidity. In this research, the effect of storing temperature and humidity on self life has been studied by measuring the contained quantity of residual stabilizer of propellant KM30Al, which are parts of 155MM propelling charge K676 and K677; the method for the measurement is acceleration aging test, and decomposition reaction equation, Eyring Equation and Berthlot Equation were used for the calculation. As result of this study, it was found that the storing temperature influenced seven times as large as the storing humidity upon the self life of the propellant KM30Al, Furthermore, especially in the high temperature region, the storing temperature had a dominant effect on the self life.

굴 패각을 채움재로 사용한 모르타르의 내화성능에 관한 연구 (A Study on Fireproof Performance of Mortar using Oyster shell as Filler)

  • 정의인;홍상훈;김봉주
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.135-136
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    • 2017
  • Oyster shell is produce by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to send. So we produced mortar test piece using grounded oyster shell powder according to Filler and reviewed Fireproof Performance.

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분급된 굴 패각을 잔골재로 사용한 모르타르의 강도특성에 관한 연구 (A Study on Strength Properties of Mortar using Classified Oyster shell as Aggregate)

  • 정의인;홍상훈;최인권;김봉주;원철희;박정훈
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.58-59
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    • 2016
  • Oyster shell is produced by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and its strength characteristic is similar to sand. So we produced mortar test piece using grounded oyster shell powder under 0.6mm, 0.6~1.2mm, 1.2~2.5mm, 2.5~5.0mm of its particle size according to fine aggregate standard and reviewed strength Properties.

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굴 패각을 잔골재로 사용한 모르타르의 물시멘트비에 따른 강도특성 (A Strength Properties According to Water cement ratio using Oyster shell as Aggregate)

  • 정의인;최인권;허민회;김봉주;원철희;최호림
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.154-155
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    • 2016
  • Oyster shell is light weighted and its strength characteristic is similar to sand. So we produced mortar test piece using grounded oyster shell powder under 0.5mm, which is a standard of fine aggregate, and reviewed strength properties according to water cement ratio. In our test, we used two kinds of oyster shell particles: below 0.6mm and 1.2~2.5mm. Water cement ratio is varied 40% to 100% and we found that flexural strength and compressive strength are decreased in higher water cement ratio.

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굴 패각을 잔골재로 사용한 모르타르의 질량비 변화에 따른 강도특성에 관한 연구 (A Study on Strength Properties of Mortar According to Mass ratio change using Oyster shell as Aggregate)

  • 정의인;유남규;홍상훈;김봉주;원철희;최호림
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.156-157
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    • 2016
  • Oyster shell is produced by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to sand. So we produced mortar test using different law of multiple proportions of grounded oyster shell powder of its particle size according to fine aggregate standard and reviewed strength Properties.

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스마트폰을 이용한 휴대용 색차계와 입도계 개발 (Development of Portable Colorimeter and Size Analyzer by Using Smartphone)

  • 유상규;박현민;김현구;김사염;송시몬
    • 한국가시화정보학회지
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    • 제17권3호
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    • pp.19-23
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    • 2019
  • The purpose of this research is to develop a facile measurement system for colorimetric analysis for zinc powder and size analyzer for zeolite particles in order to reduce the process time for their characteristic analysis. We present facile smartphone-based analysis methods to measure and estimate the size of zinc power by using colorimeteric method and the size of zeolite particles by using ImageJ program which is an open-source program. The results show a possibility of our methods to replace the previous professional analysis processes with them.

굴 패각을 골재로 사용한 모르타르의 강도특성에 관한 연구 (A Study on Strength Properties of Mortar using Oyster shell as Aggregate)

  • 정의인;유남규;허민회;김봉주;원철희;박정훈
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.193-194
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    • 2016
  • Oyster shell is produce by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to send. So we produced mortar test piece using grounded oyster shell powder under 5mm of its particle size according to fine aggregate standard and reviewed strength Properties.

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