• Macromolecular Research
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• v.14 no.2
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• pp.199-204
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• 2006

Remarkably high and stable separation performance for olefin/paraffin mixtures was previously reported by facilitated olefin transport through ${\pi}$-complex membranes consisting of silver ions dissolved in poly(hexamethylenevinylene) (PHMV). In this study, the ${\pi}$-complex formation of $AgBF_4,\;AgClO_4\;and\;AgCF_{3}SO_3$ with PHMV and their ionic interactions were investigated. FT-Raman spectroscopy showed that the C=C stretching bands of PHMV shifted to a lower frequency upon incorporation of silver salt, but the degree of peak shift depended on the counter-anions of salt due to different complexation strengths. The symmetric stretching modes of anions indicated the presence of only free ions up to [C=C]:[Ag]=1:1, demonstrating the unusually high solubility of silver salt in PHMV. Above the solubility limit, the ion pairs and higher-order ionic aggregates started to form. The coordination number of silver ion for C=C of PHMV was in the order $AgBF_4$ > $AgClO_4$ > $AgCF_{3}SO_3$, but became similar at [C=C]:[Ag]=1:1. The different coordination number was interpreted in terms of the different transient crosslinks of silver cations in the complex, which may be related to both the interaction strength of the polymer/silver ion and the bulkiness of the counteranion.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.14-22
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• 2009

In vitro cytotoxicity of 23 alkyl phenols (APs) on human cervical cancer cell lines (HeLa) was determined using the lactate dehydrogenase (LDH) cytotoxicity assay. Two different sets of descriptors were used to construct the calibration model based on Genetic Algorithm-Multiple Linear Regression (GA-MLR) based on the experimental data. A statistically robust Structure-Activity Relationships (QSAR) model was achieved ($R^2$=95.05%, $Q^2_{LOO}$=91.23%, F=72.02 and SE= 0.046) using three Dragon descriptors based on Me (0D-Constitutional descriptor), BELp8 (2D-Burden eigenvalue descriptor) and HATS8p (3D-GETAWAY descriptor). However, external validation could not fully prove its validity of the selected QSAR in characterization of the cytotoxicity of APs towards HeLa cells. Nevertheless, the cytotoxicity profiles showed a finding that 4-n-octylphenol (4-NOP), 4-tert-octyl-phenol (4-TOP), 4-n-nonylphenol (4-NNP) had a more potent cytotoxic effect than other APs tested, inferring that increased length and molecular bulkiness of the substituent had important influence on the LDH cytotoxicity.

• YAKHAK HOEJI
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• v.34 no.5
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• pp.302-310
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• 1990

A study has been made of the Korean bentonite aqueous suspension contrast with American bentonite by means of XRD IR swelling, gel formation and rheogram at various conditions such as concentration, temperature and pH. The Korean bentonite was identified as montmorillonite clay containig a small proprotion of crystoballite and mordenite, and its swelling power were acceptable for requirements of Korean pharmacopeia regulations though its values were not satisfied. Korean bentonite swelled to 10 times and American one did to 15 times compared to its bulkiness of powder. The rheogram of Korean bentonite suspension reveals bulged pseudoplatic flow with yield value at higher concentration and pseudoplastic flow without yield value at lower concentration. The higher the concentration, the greater were the apparent viscosity and hysteresis loop. Korean bentonite suspension showed insignificant temperature dependence on both apparent viscosity and hysteresis loop and it was more temperature dependent on viscosity but less on hysteresis loop than those of American sample. The pH dependence was so high on viscosity that apparent minimum value was near pH 7 and maximum value at pH 3 or 7. The hysteresis loop appeared minimum over the pH range 5-7 and maximum near pH 3 or 11. The Korean bentonite was inferior to the American bentonite in swelling volume, gel formation, thioxotropy, however, it would be possible to improve the quality of Korean bentonite by developing the method of purification for bentonite clay.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.144-153
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• 2001

The effect of crosslinking on hand of the cellulase treated Tencel fabrics was investigated. Tencel fabrics were crosslinked with DMDHEU, mechanically prefibrillated, hydrolyzed by cellulase, and treated with softener. The treated fabrics were characterized by add-on, weight loss, DP rating, WRA, strength, SEM analysis and hand measurement. As DMDHEU concentration increased, weight loss of DMDHEU/cellulase treated fabrics decreased. However, cellulase treatment decreased DP properties and strength retention. Less fibrils were observed in the cellulase treated fabrics after DMDHEU treatment than the cellulase treated ones. It was confirmed that crosslinking with DMDHEU treatment was effective to control fibrillation. At 5% of DMDHEU concentration, DMDHEU/cellulase treated fabrics showed softer, smoother and bulkier hand compared with other treated fabrics. Among mechanical properties, bending and shearing properties were decreased progressively through DMDHEU, cellulase, and softener treatment. DMDHEU treatment contributed to impart resilience, cellulase treatment to bulkiness and softener treatment to smoothness. As the treatment of DMDHEU, cellulase, and softener progressed NUMREI, FUKURAMI, and THV increased with the exception of KOSHI.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1141-1149
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• 1998

Tencel fabrics were treated with NaOH, mechanically prefibrillated, and hydrolyzed by cellulase. Softner was applied to improve hand of the treated Tencel fabrics after prefibrillation and cellulase treatment. Kawabata's Evaluation System for Fabrics(KES-FB) was used to evaluate effects of NaOH pretreatment, prebifrillation, and cellulase and softner treatments on fabric hand of the treated fabrics. Primary hand values of women's medium thick fabrics such as KOSHI, NUMERI, FUKURAMI, and SOFUTOSA, and total hand values were evaluation parameters. As the treatments of prefibrillation, cellulase, and softner progressed, values in bending and shearing properties decreased and softness and elasticity were imparted to the treated fabrics. Specifically, compressional linearity, compressional energy, and thickness of the treated fabrics increased by prefibrillation, providing bulkiness to the treated fabrics. Values indicating surface properties increased owing to fibrils formed by prefibrillation treatment, but removal of fibrils by cellulase treatment enhanced smoothness. As the fabrics were exposed to various treatments such as NaOH pretreatments, prefibrillation, and cellulase and softner treatments, NUMERI, FUKURAMI, SOFUTOSA, and total hand values increased with the exception of KOSHI, Consequently, the treated fabrics became softer, smoother, and more elastic. Especially, the NaOH pretreatment provided superior SOFUTOSA to Tencel fabrics.

• Journal of Sensor Science and Technology
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• v.14 no.6
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• pp.374-380
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• 2005

Vibration sensors have a wide scope of applications in the field of monitoring systems that needs to perceive an undesirable physical vibration before a critical failure occurs in a system, and then costly unplanned repairs can be avoided. The conventional vibration sensors developed so far have many disadvantages, such as complex manufacturing process, bulkiness, high cost, less reliability and so on. This paper reports a simple-structured vibration sensor, which has been developed using a commercialized conductive ball and silicon bulk-micromachining technology. The sensor consists of a conductive ball placed in $600{\mu}m$-deep micromachined silicon groove, in which Au thin film has been patterned using a shadow mask technique. Prior to the formation of the Au thin film, the sharp convex corner was rounded for smooth meatl deposition on the non-planar surface at the edge of the groove. The measurement results of the fabricated vibration sensor demonstrate a stable response characteristic to low-frequency vibration range ($1{\sim}30{\;}Hz$).

• The Research Journal of the Costume Culture
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• v.24 no.1
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• pp.107-113
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• 2016

The purpose of this study was to examine new-silver women's fiber and material property preferences and purchasing behaviors. The survey subjects were 115 new-silver women ranging in age from 50 to 60 years old. This study utilized a questionnaire as a measurement tool. The results of this study were as follows: First, the home ownership rate of the participants in this was 81.4%, and 54.9% of them had a bachelor's degree or higher. Therefore, they turned out to be a new silver generation with higher education and stable income and assets. Second, regarding their purchasing behaviors, it was shown that they purchased the largest amount of clothing for themselves and their spouses, children, and grandchildren at the change of seasons. Third, with regard to their average spending on clothing, when they purchased clothing for themselves, it was shown that they purchased clothing at the price of KRW 500,000 or above for themselves but not for their family members. Fourth, their favorite type of fiber was synthetic fiber, and their favorite material property was heaviness, followed by roughness, stiffness, bulkiness, and glossiness. Moreover, with regard to their favorite functional textile, it was shown that the highest percentage of them preferred vitamin textiles, followed by ocher and scented textiles.

• Korean Journal of Human Ecology
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• v.13 no.4
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• pp.609-616
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• 2004

The purpose of this study is to examine the difference of judge's gender and age groups in preference of S/S men's suit fabrics, and to analyze the relationship between the preference and the texture by gender and age group. For this study, 60 types of S/S men's suit fabrics were used with variously-composed fibers, such as wool, wool-blended, and PET, thickness, and weight. To evaluate the texture and the preference subjectively, nine ranks' semantic differential scale questions of 22 texture adjectives and preference of 4 apparel items were developed, Through the factor analysis, texture adjectives were classified into 7 categories: "stiffness," "elasticity," "bulkiness," "coolness," "smoothness," and "drapability." Depending on gender and age groups of judges, statistically significant differences on texture factors and the preference were observed. Especially, men under 30 years of age showed a higher grade of stiffness and a lower preference on pants than other groups. The relationship between the texture and the preference was different by gender and age group: Women evaluated a preference of men's suit fabrics in relation to stiffness and smoothness, whereas men did so in relation to stiffness, smoothness, coolness, and drapability. A young age group put more importance on drapability for preference of men's suit fabric.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.41-48
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• 2000

The main objective of this study was to investigate the packing state and optical properties of coated paper prepared with different coating colors by varying the blending ratio of such pigment as clay, $CaCO_3$, and plastic pigment. To evaluate the effect of packing state of pigment on the properties of coated paper, the coating thickness, which was theoretically calculated by specific gravity, and packing volume of pigment were used. It was found that there exists close relationship between the coating thickness and surface property of coated paper. For instance, the macro roughness(smoothness) of coated paper is closely related to bulkiness. Plastic pigments used in this research has a high finishing efficiency on the light weight coatings. Especially, hollow sphere pigment was very effective for improving the property of coated paper produced in this test. And when HSP was blended with $CaCO_3$the surface property such as smoothness and gloss improved significantly.

• Textile Coloration and Finishing
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• v.26 no.3
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• pp.230-236
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• 2014

The kapok fibers which are the functional fiber materials having natural hollows are environment friendly materials the demand and interest of which are increasing. The kapok fibers are environment friendly and natural hollow fibers which are 5-8 times lighter than cottons and have excellent performances in thermo keeping property, air permeability, bulkiness and resilience. In this study, the pretreatment according to the dyeing behaviors of kapok fibers were studied. Pretreatment(scouring, bleaching) were a variety of conditions. Scouring and bleaching, images of changed surfaces and cross-sections and dyeing behaviors of the dye-o-meter according to the concentration measured in meters and compared. Although the final exhaustion ratio of the kapok fibers scoured with a high concentration recipe was almost as same as that of the kapok fibers bleached with a high concentration recipe, the initial absorption speed of the kapok fibers scoured with the high concentration recipe was faster than that of the kapok fibers bleached with the high concentration recipe.