• 제목/요약/키워드: direct drying

검색결과 95건 처리시간 0.026초

공극수 추출방법에 따른 시멘트 페이스트의 수화도와 공극 특성 분석 (Evaluation of different methods to remove pore water in an early age cement paste for the degree of hydration measurement and pore structure analysis.)

  • 안유리;로양;김백중;이종구;강경인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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    • pp.245-246
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    • 2012
  • The analysis of microstructure is essential to understand the material behavior such as shrinkage, strength, and permeability. In this study, three different easy-to-apply specimen preparation methods for the mercury intrusion analysis were chosen, and their effectiveness in removing pore water and thus impeding further hydration was evaluated. As a result, it was found that the direct freeze-drying was the most effective among the three methods.

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Greenhouse Bulk 건조기에 의한 태양열이용에 관한 연구 (제2보) (Solar Energy Utilization in a Greenhouse Bulk Curing and Drying System. (II))

  • 이철환;변주섭
    • 한국연초학회지
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    • 제5권1호
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    • pp.79-85
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    • 1983
  • The greenhouse bulk curing and drying system utilization of the direct solar energy was tested to evaluate that how much fuel could be saved for curing flue-cured tobacco at the Dae Gu Experiment Station (North latitude : $35^{\circ}$49'), in 1979-1982. The air temperature and total radiation were 19.0 to 38.5$^{\circ}C$ and 1311.0 to 1412.7 cal/$\textrm{cm}^2$/day during the 4 replicated curing test, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 32% compared with the conventional bulk curing barn. We could obtain almost same utilization efficiency of solar energy in 1982 compare with normal year, mainly increasing the heat receiving area.

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Synthesis of $Ba_2SiS_4:Eu^{2+}$ Blue-Green Phosphor Prepared by Spray Drying Method Using Water Soluble Silicon Compound

  • Tezuka, Satoko;Suzuki, Yoshihito;Petrykin, Valery;Kakihana, Masato
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.243-245
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    • 2009
  • The single phase $Ba_2SiS_4$ doped with $Eu^{2+}$ was successfully synthesized by direct sulfurization of an oxide precursor prepared by a spray drying method using a novel water soluble silicon compound, which remains soluble in a given aqueous solution. The intensity of the emission peak of thus obtained $Ba_2SiS_4:Eu^{2+}$ was 1.75 times larger than that of a sample prepared by a solid state reaction method, and it approached 106% compared to one of the best commercially available YAG:$Ce^{3+}$ phosphor.

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A Comparative Study of CG CryoDerm and AlloDerm in Direct-to-Implant Immediate Breast Reconstruction

  • Lee, Jun Ho;Park, Ki Rin;Kim, Tae Gon;Ha, Ju-Ho;Chung, Kyu-Jin;Kim, Yong-Ha;Lee, Soo Jung;Kang, Soo Hwan
    • Archives of Plastic Surgery
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    • 제40권4호
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    • pp.374-379
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    • 2013
  • Background To date, various types of acellular dermal matrix (ADM) have been developed for clinical use. AlloDerm is the most familiar type of ADM to most surgeons in breast reconstruction. It is prepared by freeze-drying. CG CryoDerm is the first form of ADM that requires no drying process. Therefore, theoretically, it has a higher degree of preservation of the dermal structures than AlloDerm. We conducted this study to compare the clinical course and postoperative outcomes of patients who underwent direct-to-implant breast reconstructions using AlloDerm and those who did using CG CryoDerm. Methods We performed a retrospective analysis of the medical records in a consecutive series of 50 patients who underwent direct-to-implant breast reconstruction using AlloDerm (n=31) or CryoDerm (n=19). We then compared the clinical course and postoperative outcomes of the two groups based on the overall incidence of complications and the duration of drainage. Results The mean follow-up period was 16 months. There were no significant differences in the overall incidence of complications (seroma, infection, skin flap necrosis, capsular contracture, and implant loss) between the two groups. Nor was there any significant difference in the duration of drainage. Conclusions CG CryoDerm has the merits of short preparation time and easy handling during surgery. Our results indicate that CG CryoDerm might be an alternative allograft material to AlloDerm in direct-to-implant breast reconstruction.

소각장 폐열을 활용한 농업폐기물 열풍 건조장치 개발 (Development of Heated-Air Dryer for Agricultural Waste Using Waste Heat of Incineration Plant)

  • 송대빈;임기현;정대홍
    • 농업생명과학연구
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    • 제53권5호
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    • pp.137-143
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    • 2019
  • 본 연구에서는 단순 폐기 되는 농업폐기물(토마토, 고추, 파프리카)을 고형연료로 재활용하기 위한 열풍건조장치를 개발하고 실험을 통해 그 성능을 확인하고자 하였다. 연구를 위해 건조용량 500 kg/hr인 쓰레기소각장 폐열을 열원으로 사용하는 건조기를 제작하였다. 경상남도 진주시 농산물 시장에서 구입한 남해산 시금치를 실험원료로 사용하였다. 열교환기에서 스팀 열교환에 의해 가열된 건조공기를 열풍으로 사용하여 절단 원료 투입량(126, 250, 300 kg), 원료교반여부(수동 교반, 수동 비교반), 건조방식(건조물 정치, 건조물 이송), 건조시간(0.25, 0.5, 0.6 hr)에 따른 건조특성을 파악하였다. 투입 원료의 함수율은 85.65%로 측정되었으며, 소각장 공급 스팀에 의해 열교환기에서 가열된 건조공기온도는 건조기에 투입된 실험원료의 퇴적고에 따른 압력저항에 의해 다소 차이를 보였으며 약 108 내지 144℃로 측정되었다. 동일 건조방식, 투입량, 건조시간, 건조공기온도에서 상하층간 원료를 교반하는 하는 경우가 그렇지 않은 경우에 비해 약 2배 정도의 높은 건조속도를 보였다. 각 실험에서 건조용량은 약 500 kg/hr으로 나타났다. 국내 농산물 건조기 157개의 농업실용화재단 검사성적서를 기준으로 투입 에너지에 대한 건조 소요에너지 비를 나타내는 건조효율을 비교한 결과 국내 농산물 건조기 57.76%, 개발된 농업폐기물 건조기 33.46%로 기존 농산물 건조기에 비해 낮게 나타났다. 개발된 농업폐기물 건조기는 건조시간이 1시간 이내로 건조시간이 짧으며, 건조 중 많은 풍량이 손실되어 건조효율이 저하된 것으로 판단되었다. 소각장 폐열을 직접 건조열원으로 사용하는 경우 건조공기온도는 최저 160℃ 이상으로 예상 되는 바 건조용량이 크게 향상될 것으로 예측된다.

축열메디아 활용 직접부상방식을 이용한 하수찌꺼기의 건조기술 향상에 관한 연구 (Research on Improving Drying Technology For Sewage Waste Using Direct Flotation Using Heat Storage Media)

  • 노성일;김웅용;조성균;신현곤
    • 유기물자원화
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    • 제31권4호
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    • pp.5-11
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    • 2023
  • 본 연구는 하수 탈수찌꺼기가 건조기에 직 투입되는 경우 함수율 40~60% 구간에서 발생하는 Glue Zone에서 뭉침 및 Fouling 현상 등의 문제점 및 에너지효율 개선을 하기 위해 수행하였다. 열풍 온도는 270~300℃로 낮게, 패들타입의 부상방식과 순환되어진 축열 메디아에 탈수찌꺼기가 도포되어 열풍과의 접촉면적을 증대시켜 에너지 회수 및 가스 배출량을 감소시켰으며, 건조 찌꺼기의 함수율은 2.7~7.5%, 수분 증발열량은 608.0~690.6kcal/kg·H2O로 축열 메디아 미투입 시 수분 증발열량 714.5 kcal/kg·H2O과 비교하여 약 8.8%의 에너지 절감 효과를 확인하였다.

조미 반건조 제품 가공 공정에 따른 연어육 Texture의 변화 (Changes of Salmon Meat Texture During Semi-Drying Process)

  • 유병진
    • 한국수산과학회지
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    • 제30권2호
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    • pp.264-270
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    • 1997
  • 연어육으로써 조미반건조 제품을 가공하기 위한 기초 자료를 조사하기 위하여 가공조건에 따른 texture의 변화를 측정한 결과는 다음과 같다. 건조시간과 열풍온도가 증가할수록 연어육의 수분함량은 감소하였고, 수분감소량에 비례하여 hardness, shear stress 및 adhesiveness는 증가하였다. 연어육 건조 중에 hardness, shear stress 및 cohesiveness의 상관관계는 hardness와 shear stress는 비례하였고 hardness와 cohesiveness는 반비례관계를 나타내었다. 당장 및 염장 후, 건조시간이 증가할수록 hardness와 shear stress는 증가하였다. 관능검사 결과, 3시간 이상 건조한 당장시료의 texture가 "약간 좋다" 이상을 보였다. 가열 중의 texture 변화에 있어서는 10시간 건조한 시료가 4시간 건조시료 보다 hardness 및 shear stress 값이 높았으며, 가열시간이 증가함에 따라 10시간 건조한 시료의 hardness는 큰 변화가 없었으나 4시간 건조한 시료에서 감소하였다. Cohesiveness의 경우 가열시간이 경과함에 따라 4시간 건조시료와 대조구는 감소하였으나 10시간 건조한 시료에는 거의 변화가 없었고 adhesiveness에 있어서는 가열시간에 따른 일정한 경향을 나타내지는 않았다.

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Fabrication of Organic Nanowire Electronics by Direct Printing Method

  • 박경선;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.563-563
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    • 2012
  • We report a one-step fabrication of single-crystal organic nanowire arrays on substrates using a new direct printing method (liquid-bridge-mediated nanotransfer moulding, LB-nTM), which can simultaneously enable the synthesis, alignment and patterning of the nanowires using molecular ink solutions. Two- or three-dimensional complex structures of various single-crystal organic nanowires were directly fabricated over a large area with a successive process. The position of the nanowires can be aligned easily on complex structures because the mold is movable on substrates before drying the polar liquid layer, which acts as an adhesive lubricant. This efficient manufacturing method can produce a wide range of optoelectronic devices and integrated circuits with single-crystal organic nanowires.

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실리콘 웨이퍼 직접접합에서 내인성 Bubble의 거동에 관한 연구 (The Behavior of Intrinsic Bubbles in Silicon Wafer Direct Bonding)

  • 문도민;정해도
    • 한국정밀공학회지
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    • 제16권3호통권96호
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    • pp.78-83
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    • 1999
  • The bonding interface is dependent on the properties of surfaces prior to SDB(silicon wafer direct bonding). In this paper, we prepared silicon surfaces in several chemical solutions, and annealed bonding wafers which were combined with thermally oxidized wafers and bare silicon wafers in the temperature range of $600{\times}1000^{\circ}C$. After bonding, the bonding interface is investigated by an infrared(IR) topography system which uses the penetrability of infrared through silicon wafer. Using this procedure, we observed intrinsic bubbles at elevated temperatures. So, we verified that these bubbles are related to cleaning and drying conditions, and the interface oxides on silicon wafer reduce the formation of intrinsic bubbles.

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남자 대학생의 손 씻기 의식과 실천에 관한 연구 (A Study on the Hand-washing Awareness and Practices of Male University Students)

  • 김종규;박정영;김중순
    • 한국환경보건학회지
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    • 제35권1호
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    • pp.36-44
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    • 2009
  • Hand-washing has been recognized as a critical factor in controlling infection and cross-contamination. This study was performed to investigate hygienic behavior of male university students focusing on awareness of hand-washing, their hand washing practices, and the difference between their awareness and practices. Both a self-administered questionnaire survey and a separate direct observation in restrooms were carried out at a university campus over a four week period. In the survey, 93.6% of the responded students claimed to wash their hands after using toilet. However, just 16.9% of the observed students actually did so, according to a separate and unnoticed observational study. Among the observed students who washed their hands, 25.0% of them used soap, only 5.0% of them washed four parts of their hands, and 15.0% of them washed their hands for more than 10 seconds. Paper towel was the most common hand drying method in the direct observation and also in the survey. Significant differences between the questionnaire survey and the direct observation (p<0.0l) were found in hand-washing practices, duration of hand-washing, using soap, washing parts of the hand, and hand-drying method after using the toilet. This study indicates that there is a remarkable difference between the male university students' awareness of hand-washing and their hand-washing practices. This study reveals that there is the need for programs or campaigns to increase hand-washing practices of male university students.