• 제목/요약/키워드: moisture sorption and desorption

검색결과 17건 처리시간 0.02초

유류오염 토양의 복원을 위한 열탈착 처리기술

  • 유동준;김영웅;박용규;오방일;구자공
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.111-114
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    • 2001
  • Thermal desorption process is valuable for the remediation of oil contaminated site. The system is physical separation process by volatizing oil contaminants from soil matrixes and is not designed to provide high levels of oil destruction. The process is not incineration, because the decomposition of oil materials is not the desired result, although some decomposition may occur. The physical and chemical properties that influence the design and operation of the system include boiling points, soil sorption characteristics, aqueous phase solubility, thermal stability, contaminating oil concentration, moisture contents, particle size distribution and etc.

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저장상대습도에 따른 보리쌀의 흡습특성 (Sorption Characteristics of Barleys at Various Relative Humidities)

  • 정은영;염초애;김성곤;장명숙
    • 한국식품과학회지
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    • 제19권4호
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    • pp.331-337
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    • 1987
  • 보리쌀, 할맥 및 납작보리의 수분 흡착 특성을 $20^{\circ}C$에서 조사하였다. 상대습도 75%이상 에서의 흡습 속도 및 상대습도 44%이하에서의 탈습 속도는 모두 보리쌀>납작보리>할맥의 순서이었다. 수분 흡착 속도로부터 보리 가공품 모두에게 적용될 수 있는 실험식을 제안하였다.

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벼 상온통풍건조의 최소풍량비에 관한 연구 (Minimum Specific Airflow Rate Requirements for Natural Air Drying of Rough Rice in Korea)

  • 금동혁;박선태
    • Journal of Biosystems Engineering
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    • 제21권1호
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    • pp.60-71
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    • 1996
  • The purposes of this study were to develop a simulation model and to determine minimum specific airflow rate requirements for natural air drying of rough rice in Korea. A simulation model was developed considering energy and mass balances within grain bed, drying and rewetting rates, and hysterisis effect between sorption and desorption isotherms. As the results of validation test, the moisture contents predicted by the model agreed very well with the actual data. The criteria for determining minimum specific airflow rate requirements was that the top loom layer in the bin be dried to a moisture content below 16 percent wet basis with less than 0.5% drymatter decomposition. The minimum specific airflow rate requirements in 13 locations of Korea were presented based on the worst one among the past 7 to 13-year weather data. These requirements were also presented for all the combinations of three harvest dates and four harvest moisture contents. Specific airflow rate requirements seemed to be half by each 2 percent reduction in moisture content from 24 percent. As harvest date was delayed by 10 days from October 1, these requirements were reduced by about 20 to 40 percent.

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A Study on the Distribution and Time Dependent Change of Wood Temperature by Solar Radiation

  • Xu, Hui Lan;Kang, Wook;Chung, Woo Yang
    • Journal of the Korean Wood Science and Technology
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    • 제37권2호
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    • pp.141-147
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    • 2009
  • The fluctuation of physical properties in wood or wood composites is an important subject when the materials in building and construction. Sorption and desorption occur in wood when exposed to the open air, and the temperature distribution in wood can fluctuate as a result of changes in environmental temperature, solar radiation, humidity, and wind velocity. In this study, the temperature difference and fluctuation caused by outdoor environment among different wood species were analyzed using a numerical method. The effect on the process of heat transfer in wood caused by environmental factors was investigated using 1-dimensional partial differential equation with real boundary and initial conditions. The experimental data have been used to check the accuracy of programming code. Through analysis, it was found out that density and moisture content have a negative effect on thermal diffusivity of wood.

실리콘 표면에 증착된 다공성 알루미나의 수분 흡착 거동 (Moisture Gettering by Porous Alumina Films on Textured Silicon Wafer)

  • 임효령;엄누시아;조정호;좌용호
    • Korean Chemical Engineering Research
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    • 제53권3호
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    • pp.401-406
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    • 2015
  • 게터는 반도체와 초소형 전자패키지 소자 내부의 수소와 수증기 같은 기체를 흡착하여 기기 작동 시 방해 기체를 제거하는 기능을 한다. 본 연구에서는 재료와 공정 측면에서 높은 가격 경쟁력을 갖는 게터로, 실리콘 기판에 올라간 다공성 알루미나 구조체를 제조하는 연구를 진행하였다. 기공의 크기가 조절된 양극산화 알루미나(AAO)는 높은 비표면적을 가지며 표면에 OH-기를 다수 포함하므로 높은 효율을 갖는 수분 흡착제로 사용되었다. 등온 수분 흡탈착 곡선으로 분석한 수분 흡착도는 상대습도 35%일 때 2.02%로 우수한 성능을 나타내었다. 즉, 저온에서 사용가능하며, 추가 열원이 필요하지 않아 박막구조의 소형화가 용이하여 내부 손상 및 오염을 방지할 수 있는 게터재를 합성하였다.

솔비톨 혼합물과 글리세린 가소제에 의한 분리 대두단백질 필름의 특성연구 (Characteristics of Soy Protein Isolate Films Plasticized by Mixtures of Crystalline and Aqueous Sorbitol or Glycerin)

  • 김기명;;최원석;조성환;최성길
    • 한국식품저장유통학회지
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    • 제13권3호
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    • pp.285-291
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    • 2006
  • 가소제로서 솔비톨 혼합물의 첨가가 분리대두단백 필름의 수분흡습특성, 수분투과도, 색, 인장강도 및 신장률, 그리고 용해 특성에 미치는 영향을 조사하였다. 솔비톨 혼합물은 액상형과 결정형의 상태로 다양한 비율로 혼합하여 첨가하였고, 가소제로 글리세린을 첨가한 대조구 필름의 물리적 특성과 비교하였다. 솔비톨이 첨가된 필름은 대조구 필름에 비해 높은 인장강도를 갖는 반면 낮은 수분투과도 및 신장률을 보였다. 한편 솔비톨 첨가 형태에 따른 영향은 필름 신장률에는 유의적 차이는 보였으나 기타 수분투과도, 색, 인장강도 등의 필름특성에는 커다란 차이는 보이지 않았다. 솔비톨 첨가된 필름은 높은 수분차단 효과 및 필름강도를 갖는 대신 높은 용해성을 보여, 상업적 활용성을 증진시키기 위해서는 이를 극복하는 연구가 필요할 것으로 사료된다.

DIS에 의한 Polyethylene Glycol 함침 알로에 베라 겔의 보습 및 경피흡수 특성 (Moisturization and Transdermal Penetration Characteristics of PEGimpregnated Aloe vera Gel from DIS Processing)

  • 권혜미;허원;이신영
    • KSBB Journal
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    • 제28권5호
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    • pp.319-326
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    • 2013
  • This study was carried out to investigate the in vitro and in vivo moisturizing properties and percutaneous absorption of PEG-impregnated Aloe vera gel. The PEG-i-Aloe gel was obtained from dewatering and impregnation by soaking (DIS) of Aloe vera leaf slice. The moisturizing property of the obtained sample was evaluated by moisture determination using gravimetric method in desiccator under different RH% and by water sorption-desorption test on human skin. The transdermal penetration characteristics of PEG-i-Aloe gel was investigated by Franz diffusion cell in vitro transdermal absorption method. PEG-i-Aloe gel had high moisture retention ability and could significantly lead the enhancing skin hydration status as well as reducing the skin water loss due to the film formation as a skin barrier. The skin penetration rate of PEGi- Aloe gel at steady state was 9.76 ${\mu}g/(h{\cdot}cm^2)$ and the quantity of the transdermal absorption was 144 ${\mu}g/cm^2$ in 9 hr. The penetration mechanism was well fitted with Higuchi model ($R^2$ = 0.974-0.994). The results show that PEG-i-Aloe gel has the significant moisturizing effect and strong penetration of the animal skin. It could be used as the moisturizing additive in cosmetic skin products.