• Title/Summary/Keyword: Moisture Absorption Rate

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The Effect of Fiber Type, Compressional Resilience and Moisture Transport Properties of Fiber on the Heat Transfer of Insulating Nonwovens (섬유의 종류와 압축특성 및 수분전달특성이 보온용 부직포의 열전달에 미치는 영향)

  • 김희숙;김은애
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.4
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    • pp.647-654
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    • 1996
  • The purpose of this study was to analyze the effect of fiber type, compressional resilience and moisture transport properties of wool and polyester fiber on the heat transfer of insulation nonwovens. The results obtained were as follows: 1) Overall heat transfer of wool nonwoven was slightly higher than that of polyester nonwovens. Warmability of wool nonwoven was lower than that of polyester nonwovens. The radiative heat transfer was in the range of 11~18% of overall heat transfer in polyester nonwovens and 25% in wool nonwoven. 2) As wool nonwoven compressed, overall heat transfer was increased by increasing radiative heat transfer and wamability was decreased due to the poor compressional resilience. 3) Increasing rate of heat transfer by moisture absorption in wool nonwoven was lower than that of polyester nonwovens. Thickness and compressional resilience of wool nonwoven were reduced extremely by moisture absorption.

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The Comparison of Absorption Characteristics between High Absorbent Polymers and Cellulose (고흡수성(高吸水性) Polymer와 Cellulose의 흡수특성(吸水特性) 비교(比較))

  • Yang, In;Ahn, Won-Yung
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.2
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    • pp.36-48
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    • 1990
  • This experiment was carried out to improve the quality of high absorbent polymer which has excellent absorptivity and water retention compared to pulp and absorption sheet, through absorption characteristics-absorptive power, water retention, absorption rate, gel strength, pH, particle size, and moisture content. - of six polymers, namely, anionic polyacrylamide, cationic polyacrylamide, polyacrylic, acid polyvinyle alcohol 500, and 1500, and a-cellulose. and to examine the possibility of substitution of amide groups for carboxyl group and/or hydroxyl group which were commercial high absorbent polymer by comparing the absorption characteristics of the polymers. Polyacrylamide has high absorptive power and water retention, but has low gel strength and poor absorption rate. The rest of polymers were similiar to ${\alpha}$-cellulose in every respect. Thus, polyacrylamides could be replaced with polyacrylic acid and polyvinyl alcohol which are presently a high absorbent polymers. In comparing the absorption characteristics and the absorptive power of the polymers-anionic polyacrylamide, cationic polyacrylamide, polyacrylic acid, polyvinyle alcohol. a-cellulose-the absorptive power was in inverse proportion to the gel strength and absorption rates, affected by the particle size and pH change.

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Characteristics of Water Vapor Sorption Phenomena of Powdered Foods (건조분말 식품의 수분 특성에 관한 비교 연구)

  • 박길동;김동원
    • Journal of Ginseng Research
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    • v.6 no.1
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    • pp.30-37
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    • 1982
  • This study was conducted to investigate the water vapor permeability of packaging film, Al- foil laminated paper, and sorption properties of dehydrated and powdered foods. The results are as fellows. 1. Absorption rate of each products was greately affeoted by physicochemical properties of foods rather than initial moisture contents of the products. 2. The absorption rate of each products were in the order of freeze dried coffee, spray dried coffee, freeze drie4 ginseng extract, spray dried ginseng extract, ginger tea, black tea, citrus juice Powder and ssang wha tea. 3. Most of the products such as freeze dried coffee, spray dried coffee, freeze dried ginseng extract, ginger tea and black tea have shorter than a month of shelf life. 4. The stability of the products were greatly affected by its desorption properties than the degree of desorption of moisture. 5. Water vapor permeability of packaging materials which are laminated Al-foil with polythylene and glassin paper were mainly affected of thickness of Al-foil and polyethylene.

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

  • Kwon, Oh-Kyung;Yi, Chang-Mi;Sung, Woo-Kyung
    • Fashion & Textile Research Journal
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    • v.1 no.2
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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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Qualities Analysis of Domestic Soybean Cultivars (국내산 두류 품종에 대한 품질 분석)

  • Yu, Kwang-Won;Bae, Yun-Jung;Bae, Yu-Jung;Joo, Ga-Young;Kim, Chae-Young;Yun, Ji-Hye;Lee, Kyung-Haeng
    • The Korean Journal of Food And Nutrition
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    • v.33 no.6
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    • pp.666-671
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    • 2020
  • To analyze the quality characteristics of soybean (Glycine max), the approximate analysis, physical properties, mineral and free sugar content of domestic soybean cultivars were analyzed. The moisture content was about 9.15~11.84%. The fat content of Cheonga, Taekwang, and Jinpung cultivars were 17.93~18.37%, which was significantly higher than that of others. Protein content of Cheonga and Seonyu were 36.15~36.70%, significantly higher than that of others. As for the weight and shape of soybeans, the Daewon was the largest allele, and the seed cover ratio was the highest in the Seonyu. In terms of water absorption rate, the Seonyu showed the highest absorption rate at 246.19%, and the Daewon showed the lowest absorption rate. Soaked soybeans had a hardness of 2.80~4.73 kg/㎠, which did not show low hardness in the sample with high moisture absorption. The grinded soybeans showed higher lightness and yellowness values than the raw soybeans, and the redness was decreased. Soybean minerals contained high K, P, Mg, and Ca content. Overall, The Taekwang contained more minerals than others. Stachyose, sucrose, glucose and fructose were detected as free sugars in soybeans. The total free sugar content of Taekwang was the lowest at 3.47%, and the Cheonga (6.80%) was the highest.

Effect of Immersion Temperatures and Times on Moisture Absorption and Germination of Cryptomeria japonica Seeds (침지 온도와 시간이 삼나무 종자의 수분흡수 및 발아에 미치는 영향)

  • Choi, Chung-Ho;Cho, Kyung-Jin;Tak, Woo-Sik
    • Korean Journal of Plant Resources
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    • v.20 no.5
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    • pp.398-403
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    • 2007
  • This study was carried out to enhance germination of the seed by different immersion temperatures(15, 20, 25, 30 and $35^{\circ}C$) and times(1, 6, 12, 18, 24, 36 and 48 hours) in Cryptomeria japonica that is a major plantation species in the southern Korea. Optimum germination temperature was between $20^{\circ}C$ and $25^{\circ}C$, and the lowest germination was observed at $35^{\circ}C$ Moisture absorption increased with increasing immersion time as a whole and was high at $30^{\circ}C$ and $35^{\circ}C$. Initial moisture absorption rate was highest at $30^{\circ}C$ whereas was lowest at $15^{\circ}C$ Moisture absorption rate constant was also high at $30^{\circ}C$ and $35^{\circ}C$, however, it was relatively low at $15^{\circ}C$ and $20^{\circ}C$ Germination was the highest when the seeds were immersed for 48 hours at $30^{\circ}C$. In mean germination time(MGT) the seeds immersed for 48 hours at $30^{\circ}C$ did not differ from non-treatment, while the others showed higher values than non-treatment. Consequently, germination could be enhanced and MGT was kept by optimum immersion temperature and time.

Dyeing Properties of Nylon 6 Ultramicrofiber (나일론 6 초극세 섬유의 염색성)

  • ;;;Tomiji Wakida
    • Textile Coloration and Finishing
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    • v.14 no.6
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    • pp.319-327
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    • 2002
  • Nylon 6 ultramicrofiber(UMF, monodenier 0.074d) and regular staple fiber(monodenier 2.05d) were dyed with acid and disperse dyes to investigate the effect of the difference of the fiber fineness. Also X-ray diffraction pattern, birefringence, DSC thermogram, moisture regain and water absorption of these fibers are measured. The dyeing rate of nylon UMF with acid dyes is increased compared with that of regular fiber, but not increased for disperse dyes. Also the saturation dye uptake of UMF with acid dyes is higher than that of regular fiber, while it is unchanged for disperse dyes. The moisture regain of UMF is similar to the regular fiber, whereas the water absorption of UMF is two times th그n that of the regular fiber. The crystallinity percentage of UMF is higher than that of regular fiber.

The variations of AC dielectric breakdown strength of epoxy composites due to boiling absorption (비등흡수에 따른 에폭시 복합체의 교류 절연파괴강도의 변화)

  • 이덕진;김경민;김탁용;손인한;신성권;김경환;김재환
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.529-531
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    • 1999
  • In this Paper, the variable dielectric breakdown strengths of epoxy composites were investigated at belling absorption condition in order to observe the influences of moisture in out door use. Also. in order to improve withstand voltage properties at moisture absorbtion condition, IPN(interpenetrating polymer network) method was Introduced and the Influence was investigated. As Adding filler(SiO$_2$) classified by o(phr), 50(phr) and 100[phr] to two kinds of matrix resin, six kinds of specimens were manufactured. As a result, it was confirmed that dielectric breakdown strength wer degraded with boiling time and filer content increasing. But, it was confirmed that dielectric breakdown strength degrading rate were lowered by the Improvement of adhesion strength in IPN specimens.

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Effects of Gamma-Irradiation on the Water Absorption Property of Black Soybeans (감마선 조사가 검정콩의 수분흡수 특성에 미치는 영향)

  • 김종군
    • Journal of the Korean Home Economics Association
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    • v.30 no.3
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    • pp.101-117
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    • 1992
  • Effects of gamma irradiation(2.5∼20kGy) on water absorption property was studied for a local variety of black soybeans. In water absorption patterns of black soybeans, the time to reach a fixed moisture content was reduced depending on the increment of water soaking temperature and irradiation dose. Irradiation at 2.5∼10kGy resulted in the reduction of soaking time of black soybeans by about 1∼3 hours and the increase of hydration capacity by 10∼20%, respectively, compared to the nonirradiated control black soybean. The water uptake rate constant of the irradiated black soybean difinitely increased with the increase of dose levels and water soaking temperature. The activation energy for water absorption and z-value were lower in the irradiated black soybeans than in the nonirradiated control black soybean. The efficacy of water absorption property in the irradiated black soybeans was also recognized after one year of storage at room temperature.

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