• 제목/요약/키워드: water absorption properties

검색결과 1,314건 처리시간 0.029초

마직물 및 마혼방직물의 온열특성에 대한 흡습의 영향 (The Effect of Absorption Water on Thermal Properties of Pure Linen and Linen Blended Woven Fabrics)

  • 권오경;이참미;성우경
    • 한국의류산업학회지
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    • 제1권2호
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    • pp.160-165
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    • 1999
  • The thermal properies of the pure linen fabrics available in the market and linen blended woven fabrics were measured at the moisture content of 0%, 20%, 40% and 60% using KES-F7 system (Thermo Iabo II type). The experimental properties were statistically analyzed by the rate of water absorbent. The main results were as follows; There is a positive correlation between the thermal insulation value (TIV) and thickness of pure linen fabrics and linen blended woven fabrics by water absorption. Whereas an negative correlation exists between the TIV and cover factor. There is a high positive correlation among the thermal conductivity (k), thickness and weight of pure linen fabrics and linen blended woven fabrics by water absorption. Wherase a high negative correlation exist between the k and air' permeability (Ap). There is a high positive correlation between the feeling of warmth/coldness and bulk density of pure linen and linen blended woven fabrics by water absorption. Wherase a high negative correlation exists between the feeling of warmth/coldness and porosity. There is a negative correlation between TIV and $q_{max}$ of pure linen fabrics and linen blended woven fabrics. The higher the rate of water absorbent, the lower the TIV. This means that TIV decreases by water absorption. As for the thermal property by rate of water absorbent $q_{max}$ and k increase by water absorption and reach max-value at 60% rate of water absorbent. The TIV decreases by water absorption and has +value at 0% rate of water absorbent, whereas it has -value with a feeling of coldness at 20%, 40%. and 60% rate of water absorbent.

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수정진동자 미세저울을 이용한 방식도막의 물 흡수 측정 (Measurement of Water Absorption in Anticorrosive Organic Coatings Using Quartz Crystal Microbalance (QCM))

  • 이근대;도윤정;김진호;박성수;홍성수;서차수;박진환
    • 한국해양공학회지
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    • 제17권6호
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    • pp.77-82
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    • 2003
  • The absorption of water into an anti-corrosive organic coating, such as alkyd and urethane resin coating, was investigated, using a quartz crystal microbalance (QCM). Anticorrosive properties of the coatings were also measured, by means of electrochemical impedance spectroscopy (EIS). The overall absorption of water in the coating is determined by the chemical nature of resin, and decreases with increasing thickness. The enhancement of anti-corrosive performance, through increase of coating thickness, was more remarkable in the case of the coating that hadlower equilibrium water absorption. The absorption kinetics curves were Fickian in nature. The EIS analysis confirmed that the resin, having lower equilibrium water absorption, shows higher anti-corrosive performan.

콩의 종류와 건조 방법에 따른 비지 분말의 이화학적 특성 (Physicochemical Properties of Soybean Curd Residue Powder by Different Soybean and Drying Methods)

  • 김은지;정희남
    • 한국식생활문화학회지
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    • 제38권5호
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    • pp.356-364
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    • 2023
  • This study compared the physicochemical properties of soybean curd residue and black soybean curd residue produced by hot air-drying and freeze-drying. Regardless of drying method, the crude protein, crude ash, crude fiber contents, pH, L, a, b color values and water soluble index were higher in soybean curd residue, whereas total polyphenol contents and antioxidant activity were higher in black soybean curd residue. Significant differences in water absorption index, oil absorption capacity and emulsion activity were observed between soybean curd residue and black soybean curd residue in freeze-drying. On the other hand, the emulsion stability was not significant difference in both hot-air drying and freeze-drying. The crude protein and crude fiber contents of soybean curd residue were not significant difference between hot-air drying and freeze-drying. Freeze-drying resulted in higher crude ash contents, pH, water absorption index, water soluble index, oil absorption capacity, emulsion activity and emulsion stability than hot-air drying. Hot-air drying have caused significantly higher water contents, water activity, total polyphenol contents and antioxidant activity in soybean curd residue than freeze-drying. In conclusion, soybean type and drying methods affect the physicochemical and quality characteristics of soybean curd residue, which could be important factors in the manufacture of processed foods.

흡습된 수냉각 발전기 고정자 권선의 전기적 특성 (Electrical Properties of Wet Bars in Water-cooled Generator Stator Windings)

  • 김병래;김희동
    • 한국전기전자재료학회논문지
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    • 제25권10호
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    • pp.817-823
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    • 2012
  • Insulation breakdown of water-cooled generator stator windings occurs frequently due to leakage of cooling water and absorption into the insulation material. Leakage and absorption problems of water-cooled stator windings are often found during regular preventive maintenance. To evaluate cooling water leakage and absorption, diagnostic tests were performed on two water-cooled turbine generators, which have been in service for 13 and 17 years, respectively. The test results of the measured electrical properties such as dissipation factor($tan{\delta}$), capacitance and AC leakage current for water-cooled generator stator windings with wet bars are reported in this paper.

열화상카메라를 이용한 직물의 물 흡수 및 건조 특성에 대한 실험 연구 (Experimental Study on Water Absorption and Drying Characteristics of Various Fabrics using IR Camera)

  • 김정배
    • 한국분무공학회지
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    • 제28권1호
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    • pp.10-15
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    • 2023
  • Recently, various types of towels and dishcloth dryer products are being widely distributed in Korea. Evaluation methods for water absorption properties of various fabrics have been developed, and there are many studies using them. This study newly intended that whether it is possible to obtain data that can quantitatively analyze the water absorption characteristics of various fabrics, to show the correlation between the water absorption height and the amount of water (water holdup) absorbed, and to experimentally suggest the applicability to evaluate the drying capacity of towel dryer using IR camera. Through these experiments, it was confirmed that quantitative data on the water absorption height of various fabrics can be measured using an IR camera and can be clearly applied to the performance evaluation of actual products.

Mechanical Properties and Water Absorption of Rice Starch-Filled Linear Low Density Polyethylene

  • Wahab, Mohammad A.;Mottaleb, Mohammad A.
    • Macromolecular Research
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    • 제9권6호
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    • pp.297-302
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    • 2001
  • Rice starch was incorporated into linear low density polyethylene (LLDPE) using a Brabender Plastic-Corder internal mixer at a temperature of 140$\^{C}$ and 40 rpm. The starch loading was varied from 0 to 30% with 5 intervals. Studies on brabender torque development, mechanical properties and water absorption were investigated. The starch loading did not influence the brabender torque significantly. With respect to mechanical properties; the tensile strength and elongation at break decrease with increasing starch loading. The Young's modulus also increases with the starch filling. Mechanical properties were deteriorated as the starch absorbed moisture. The rate of water absorption was dependent on the starch filling in the composites. The scanning electron microscope (SEM) analysis was performed for the tensile fracture surfaces and it revealed the starch agglomeration and a poor dispersion of starch in the LLDPE matrix.

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Capillary Water Absorption Properties of Steel Fiber Reinforced Coal Gangue Concrete under Freeze-Thaw Cycles

  • Qiu, Jisheng;Zheng, Juanjuan;Guan, Xiao;Pan, Du;Zhang, Chenghua
    • 한국재료학회지
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    • 제27권8호
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    • pp.451-458
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    • 2017
  • The service life of coal gangue concrete(CGC) strongly depends on the capillary water absorption, this water absorption is susceptible to freeze-thaw cycles. In this paper, the cumulative water absorption and sorptivity were obtained to study the effects of 0, 0.5, 1.0, and 1.5 % steel fiber volume fraction added on the water absorption of CGC. Sorptivity and freeze-thaw tests were conducted, and the capillary water absorption was evaluated by the rate of water absorption(sorptivity). Three prediction models for the initial sorptivity of steel fiber reinforced coal gangue concrete(SFRCGC) under freeze-thaw cycles were established to evaluate the capillary water absorption of SFRCGC. Results showed that, without freeze-thaw cycles, the water absorption of CGC decreased when steel fiber at 1.0 % volume fraction was added, however, the water absorption increased with the addition of 0.5 or 1.5 % steel fibers. Once the SFRCGC specimens were exposed to freeze-thaw cycles, the water absorption of SFRCGC significantly increased, and 1.0 % steel fiber in volume fraction added to CGC caused the lowest water absorption, except for the case of the sample without steel fibers added. The CGC with steel fiber at 1.0 % volume fraction performed better. The SFRCGC has a strong response to freeze-thaw cycles. Results also showed that the linear function prediction model is practical in the field of engineering because of its simple form and a relatively high precision. Although the polynomial prediction model presents the highest computation precision among the three models, the complicated form and too many coefficients make it impractical for engineering applications.

Determining the Water Absorption and Rheological Properties of Rye Dough Made Using the Planetary Mixer P 600

  • Kim, Mun-Yong;Freund, Walter;Chun, Soon-Sil
    • Food Science and Biotechnology
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    • 제18권2호
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    • pp.456-462
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    • 2009
  • In comparison to processed wheat flour products, there is no established method for determining the water absorption of rye flour. The aim of this study was to work out a method using the Planetary mixer P 600 for the determination of water absorption (WA) and the rheological properties in rye dough made from rye flours of 4 different types (I-IV). In the correlation analysis showed that WA had positive correlation with ash, beginning of gelatinization, $125-160{\mu}m$ particles, sedimentation values at 20 and 25 min, bread yield, pH, and total titratable acidity, but had negative correlation with initial viscosity, gelatinization maximum, viscosities on swelling at 25, 28, and $31^{\circ}C$. The WA determined by the Planetary mixer P 600 agreed well with the experimental baking tests.

Physical and Mechanical Properties of Sawdust Board Made of Thinning Logs (II) - The Effect of Density and Additive Quantity of Powder Phenolic Resin -

  • Oh, Seung-Won
    • Journal of the Korean Wood Science and Technology
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    • 제31권3호
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    • pp.17-23
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    • 2003
  • As a fundamental study of developing sawdust board from thinning softwood logs from three species (Pinus densiflora S. et Z., Larix leptolepis G. and Pinus koraiensis S. et Z.), this study examined the effect of board density and resin content on physical and mechanical properties of sawdust board. As the board density increase, thickness swelling, bending strength, and Brinell hardness increased while water absorption decreased. With increasing the resin content, the bending strength and hardness increased while water absorption and thickness swelling decreased. The board made of L. leptolepis was slightly low in its water absorption, and the one made of P. koraiensis was a little high in its bending strength, while there was no definite difference between each kind of trees in their hardness values.

MMT 첨가에 따른 Polyamide/MMT 나노복합체의 흡습 특성 (Effect of MMT on Anti-Water Absorption of Polyamide/MMT Nanocomposites)

  • 박상철;김호겸;민경은
    • 폴리머
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    • 제37권1호
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    • pp.113-120
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    • 2013
  • Pilot scale에서의 나노복합체의 상용화를 위해 용융 삽입법을 적용하고 이축 압출기로 제조한 polyamide/MMT 나노복합체의 흡습 특성을 연구한 결과, MMT 도입으로 수분 흡수율이 감소되었으며 그에 따라 치수 안정성이 향상되었다. 굴곡강도 및 탄성률은 수분 흡수율이 증가함에 따라 저하되었으며, 이로부터 MMT의 도입은 강도 향상효과와 함께 흡습방지를 통한 강도 저하 억제효과도 보이는 것으로 조사되었다.