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991.
The application of a degassing system to mercerization process was investigated. It was found that the physical properties
of cotton fabrics mercerized in the degassed NaOH solution were superior to those mercerized in NaOH solution. The degree
of penetration of the degassed water was examined by measuring wicking height. The wicking height in the degassed water without
the wetting agent is higher than that of the saturated water with 0.1 % of wetting agent. 相似文献
992.
993.
Siloxylated polypropylene fibers composed of polypropylene (PP) and aluminosiloxane (AS) were prepared by melt blending followed by spinning. The effects of blend compositions on the thermal behaviors, surface and tensile properties of PP/AS blend fibers were investigated by DSC, WAXD, SEM, static honestometer, etc. The heat of fusion of PP/AS blends decreased with increasing AS contents. In addition, the peak intensity of PP/AS blends in X-ray diffraction patterns decreased with increasing AS contents. It was observed that the silicone molecules exist and well distribute on the surface of siloxylated polypropylene fibers. From the results of the half-life period measurements, the anti-static properties of PP fibers siloxylated with AS was found to be significantly modified. 相似文献
994.
Boong Soo Jeon 《Fibers and Polymers》2005,6(4):332-335
The fibrogram theory is newly derived from the superposition principle of the conventional staple diagram, in which the left-hand
ends of the fibers have to share a common starting point in order for the fiber length distribution to be measured, and the
right-hand ends of the fibers form points. It is shown that the fibrogram is the staple diagram of the fiber sample having
different random starting points, as well as the double cumulative distribution function of the frequency length function
in the length biased sample. Also, the various means, viz. the numerical mean length, numerical mean length in median, length
biased mean length, and length biased mean length in median, and the various upper half means, viz. the numerical upper half
mean length, numerical upper half mean length in median, length biased upper half mean length, and length biased upper half
mean length in median, are discussed in relation to the cotton blending process. 相似文献
995.
Kwon Sun Lee Beom Soo Lee Young Hwan Park Yoon Chul Park Yong Min Kim Sung Hoon Jeong Sung Dong Kim 《Fibers and Polymers》2005,6(1):35-41
Research and development of nano fiber products is very active over the world. Physical characteristics and dyeing properties
of nylon 66 nano fiber were investigated in this study. X-ray diffraction, DSC, analysis of amino end group, and water absorption
were performed to get information concerning physical properties of nano fiber. Nylon 66 nano fiber was dyed with high molecular
mass acid dyes. Effects of dyeing temperature, pH of dyeing solution, and concentration of acid dyes on dyeing properties
such as rate of dyeing and the extent of exhaustion, were examined and compared to those of regular fiber. It was found that
nano fiber adsorbed acid dyes at lower temperature, got rapidly dyed, and its extents of exhaustion at specific dyeing temperature
were higher than regular fiber. It was also observed that nano fiber could adsorb a large amount of acid dye without a significant
loss in the extent of exhaustion. Washing fastness of the dyed nano fiber was lower by 1/2∼1 grade, light fastness by 1 grade
than the dyed regular fiber. 相似文献
996.
The purpose of this study was to compare the subjective fabric hand evaluation and wear comfort of PET treated by Ultraviolet
and to evaluate the subjective results from the investigation of microclimate temperature. The subjective hand evaluation
was performed by 20 subjects (age: 20–25) with 5-point scale questionnaires to investigate the change of PET knit fabrics
treated for different times, specifically, 0, 30 and 90 minutes. The questionnaires were composite with 8 questions; roughness,
smoothness, wetness, stiffness, coolness, touch, preference, and comfort. In order to evaluate sensations of wear comfort,
we made garments with UV treated fabric and five female students were tested. They walked at the speed of 6.7 km/hr for 15
minutes in an environment, which was controlled at 29°C, 75±5 % RH. Before and after exercising, the microclimate under clothing
and subjective wear comfort was measured. The results of subjective evaluation of fabric hand were that untreated and treated
for 30 minutes PET were recognized as similar and have a good evaluation on comfort, preference, and touch. According to the
result of wear comfort, clothing treated by UV for 90 minutes had the lowest value on the thermal and humidity sensations.
In addition, the value of tactile and comfort sensation was the highest on the clothing treated by UV for 90 minutes. In the
case of objective evaluation, PET treated for 90 minutes was the lowest on microclimate humidity. PET irradiated by UV for
90 minutes was more ‘cool’ in thermal sensation and more ‘dry’ in wet sensation. Accordingly, it was consistent with the result
of subjective wear comfort. 相似文献
997.
Alizarin-series dyes (alizarin, alizarin red S, alizarin yellow GG, or mordant orange) are grafted onto shape memory polyurethane (PU) through an allophanate bonding, and the photoluminescence and the low-temperature flexibility of the resulting PUs are tested. The PU is mainly composed of 4,4′-methylenebis(phenylisocyanate) (MDI), poly (tetramethyleneglycol) (PTMG), and 1,4-butanediol (BD), and the dye is connected, through another MDI, to the carbamate moiety of the PU chain. The PUs with different dye contents are characterized, and their shape recovery and photoluminescence properties are compared. With respect to the tensile mechanical properties, the maximum stress increases up to 50 MPa, and the strain remains above 1000 % even after the dye is grafted onto the PU. The shape recovery is as high as 99 %, and the shape retention improves as the dye content increases. Finally, the photoluminescence of the PUs is demonstrated by the luminescent light emission test, and the dye-grafted PU shows excellent low-temperature flexibility compared with that of linear PU. 相似文献
998.
Gram-negative marine bacteria can thrive in harsh oceanic conditions, partly because of the structural diversity of the cell wall and its components, particularly lipopolysaccharide (LPS). LPS is composed of three main parts, an O-antigen, lipid A, and a core region, all of which display immense structural variations among different bacterial species. These components not only provide cell integrity but also elicit an immune response in the host, which ranges from other marine organisms to humans. Toll-like receptor 4 and its homologs are the dedicated receptors that detect LPS and trigger the immune system to respond, often causing a wide variety of inflammatory diseases and even death. This review describes the structural organization of selected LPSes and their association with economically important diseases in marine organisms. In addition, the potential therapeutic use of LPS as an immune adjuvant in different diseases is highlighted. 相似文献
999.