• Corrosion Science and Technology
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• 제7권2호
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• pp.69-76
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• 2008

Common methods for large scale hydrogen production, such as steam reforming and coal gasification, also involve production of carbonaceous gases. It is therefore necessary to handle process gas streams involving various mixtures of hydrocarbons, $H_2$, $H_2O$, CO and $CO_2$ at moderate to high temperatures. These gases pose a variety of corrosion threats to the alloys used in plant construction. Carbon is a particularly aggressive corrodent, leading to carburisation and, at high carbon activities, to metal dusting. The behaviour of commercial heat resisting alloys 602CA and 800, together with that of 304 stainless steel, was studied during thermal cycling in $CO/CO_2$ at $650-750^{\circ}C$, and also in $CO/H_2/H_2O$ at $680^{\circ}C$. Thermal cycling caused repeated scale separation, which accelerated chromium depletion from the alloy subsurface regions. The $CO/H_2/H_2O$ gas, with $a_C=2.9$ and $p(O_2)=5\times10^{-23}$ atm, caused relatively rapid metal dusting, accompanied by some internal carburisation. In contrast, the $CO/CO_2$ gas, with $a_C=7$ and $p(O_2)=10^{-23}-10^{-24}$ atm caused internal precipitation in all three alloys, but no dusting. Inward diffusion of oxygen led to in situ oxidation of internal carbides. The very different reaction morphologies produced by the two gas mixtures are discussed in terms of competing gas-alloy reaction steps.

• 한국입자에어로졸학회지
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• 제5권4호
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• pp.189-197
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• 2009

Wet-type particulate removal system is employed in most of ironmaking processes. These de-dusting systems require additional downstream aggregates for treatment of water and for drying of the collected slurry. Thus dried slurry can be pressed in shape of briquettes and recycled in the steelmaking process. Different from the wet-type, the dry-type particulate removal systems generate no slurry. A high-temperature, high-pressure de-dusting system with inertial inlet was developed. The target application of this system was to remove particulate matter generated from the novel ironmaking process and other steelmaking processes. In this study we conducted tests with this newly developed system to evaluate the performance of the silica-carbide (SiC) ceramic filters. In addition, for purpose of comparison, we also conducted tests with a unit which has conventional direct inlet. Fe-Particles collected from the novel ironmaking process were used in our tests as test dusts. The temperature and the pressure were kept constant at their respective values $800^{\circ}C$ and $3kg_f/cm^2$.

• 약학회지
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• 제5권1호
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• pp.31-36
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• 1960

The importance of enteric coating technique among the pharmaceutical firms has recently risen very significantly. This study of enteric coating bases was made in order to determine the most suitable bases and dusting powders. Materials and equipment used in this experiment are shown in table 1 and kinds of enteric coating bases and their formulas are shown in table 2. The evaluation of the suitability for enteric coating bases and dusting powder was made by disintergration test after measuring the thickness of the enteric coated layer as shown in the tables 4 and 5. Based on the results of this study, the base D(shellac 20 Gm, anhydrous lanoline 5 Gm, 96% alcohol 75 ml) and the base E (shellac 10 Gm, cetyl alcohol 10 Gm. acetone 80 ml) are selected among the 8 kinds of bases studied in a preliminary test and it was found that Mg-stearate and CA-stearate were in most suitable dusting powders among the 6 kinds studied for the bases D and E. Further study on base D and E was carried out by varying the proportions of the materials which were the original constituents of bases D and E. According to the result of this further study shown in table 6, the shellac 15 Gm cetyl alcohol 5 Gm Acetone 80 ml of base E is recommended as the most suitable dusting powder.

• 베이커리
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• 7호통권444호
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• pp.146-146
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• 2005

제품을 만들다보면 기대했던 대로 제품이 나오지 않거나 여러가지 궁금한 점들이 많이 생기게 마련이다. 이럴 땐 주저 없이 '테크닉 상담실"의 문을 두드려 보자. 전문가의 컨설팅을 통해 생산 현장에서 마주치는 여러 가지 기술 문제에 대해 명쾌한 해결을 도와준다.

• 한국전자통신학회논문지
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• 제7권5호
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• pp.1125-1131
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• 2012

농촌 노동력의 급격한 감소 및 고령화에 따라 저가의 농업로봇의 개발이 시급한 과제가 되어왔다. 본 논문에서는 농업용 방제 로봇의 H/W제어구조 및 S/W 플랫폼 개발에 대하여 기술한다. 개발된 로봇은 2 축의 캐터필러형 구동부와 2축의 방제기구 제어부를 구동부로 갖추고 있다. H/W 제어구조로써, 임베디드 XPE 기반 로봇 제어부, 원격 조종부, 그리고 센서 제어부로 구성된다. SW 플랫폼에서는 태스크 매니저, 원격 영상 및 데이터 통신을 위한 TCP-IP 통신 프로세스, 구동부 제어 프로세스, 위치 및 환경 인식 프로세스, 센서제어부 프로세스 등 5개의 프로세스가 동시에 동작한다. 개발된 농업용 원격 방제로봇을 필드테스트를 통하여 유용성을 시험하였다.

• 한국세라믹학회지
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• 제38권1호
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• pp.68-73
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• 2001

Active belite cement clinker 합성을 위하여 안정제로 borax (3 wt%)를 사용하였으며, 1300, 1350, 140$0^{\circ}C$에서 소성하고, 각각의 소성온도에서 아세톤 급냉, 공냉, 로냉의 3가지 방법으로 냉각속도를 달리하여 합성하였다. 클링커의 특성분석은 TG-DTA, XRD, FT-IR, SEM-EDS로 조사 분석하였으며, free-CaO 함량은 KSL 5120의 ethylene glycol법으로 정량하였다. Borax(3 wt%)를 첨가한 시료의 시차열분석에서 ${\gamma}$상으로의 전이는 관찰되지 않았으며, 각각의 소성온도와 냉각속도에 따른 free-CaO 분석에서 0.07~0.14%의 범위로 낮게 나타났으며, borax가 첨가되지 않은 시료는 140$0^{\circ}C$에서 소성하고 급냉시켰지만 ${\gamma}$상으로 전이되어 dusting 현상을 나타내었다. Borax(3 wt%) 첨가된 시료의 SEM 미세구조는 140$0^{\circ}C$에서 소성하고 급냉시켰지만 ${\gamma}$상으로 전이되어 dusting 현상을 나타내었다. Borax(3 wt%) 첨가된 시료의 SEM 미세구조는 140$0^{\circ}C$에서 소성된 모든 시료와 135$0^{\circ}C$에서 소성하고 급냉과 공냉시킨 시료는 type I belite, type III belite($\alpha$상) 구조를 나타낸다. 135$0^{\circ}C$에서 소성하고 로냉한 시료와 130$0^{\circ}C$에서 소성된 모든 시료는 type II belite($\beta$상) 구조를 나타내었다.

• 대한토목학회논문집
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• 제3권2호
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• pp.73-85
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• 1983

목제(木製)거푸집을 사용한 콘크리트구조물(構造物)에서 거푸집을 제거했을 때 콘크리트표면에 경화불량(硬化不良)으로 인한 결함부분을 종종 발견하게 된다. 이러한 콘크리트 표면의 경화불량현상(硬化不良現象)을 거푸집에 도포(塗布)하는 박리제(剝離劑)나 합판 제조시 사용되는 접착제(接着劑) 또는 포르말린 등의 영향으로만 일반적으로 생각해 왔다. 그러나 실험결과 목제거푸집을 사용한 콘크리트 표면의 경화불량현상(硬化不良現象)은 이런 원인보다는 오히려 목제의 종류나 목제의 보관상태 특히 태양광선(太陽光線)에 장시간 노출시킨 거푸집을 사용했을 때 심한 영향을 미침을 알 수 있었다. 그래서 목제거푸집을 사용한 콘크리트표면의 경화불량현상(硬化不良現象)을 방지하기 위한 대책에 대해서도 실험을 통하여 고찰했다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.706-707
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• 2006

Premixes treated with a binder, such as in the FLOMET process, exhibit better flow, reduced dusting and segregation and improved productivity and part consistency compared to conventional premixes. The binder treatment is highly suitable for high performance P/M applications which often require premixes containing very fine alloying additives and excellent die filling characteristics. With this process, various binders and lubricants can be utilized in order to make premixes with unique properties. In this paper, the characteristics and performances of bonded premixes are reported.

• Journal of Ginseng Research
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• 제14권1호
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• pp.50-56
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• 1990

Root-rot of ginseng caused by Fusarium solani is one of the most obstacles to ginseng cultivation. We evaluated some inoculating techniques of ginseng with Fusarium solani, for selection of disease resistant breeding lines. The most effective inoculating techniques evaluated were inserting toothpicks colonized by F. solani into the seedling roots in laboratory test and dusting seedlings with vermiculite after dipping in conidial sllspension and then replanting method in field test. The resistance to diseased by F. solani was lines of 82022 and 82066 in laboratory test. 82920-1 and 78093 in field test.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2011년도 자성 및 자성재료 국제학술대회
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• pp.82-83
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• 2011