• Fibers and Polymers
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• v.7 no.1
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• pp.8-11
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• 2006

It has been reported for several decades that microbes, which naturally contaminate cotton fibres during crop growth and subsequent storage can have an adverse effect on the structural quality of cotton lint. Although several studies have analysed the relationship between numbers of Gram-negative bacteria or bacterial endotoxin and particular physical properties, these studies have been limited to cotton from the United States, and the possible effects of fungal contamination have not been examined in detail. This study quantified the Gram-negative bacteria and fungal cells, as well as measuring concentrations of bacterial endotoxin and fungal glucan, on cotton lint samples from international sources. Spearman's rank correlation coefficients calculated between these results and quality data analysed by an automated testing instrument revealed several significant correlations. Findings included inverse correlations between the biological contamination parameters and fibre elongation, micronaire and reflectance. The possible causes and implications of these findings were also discussed.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.4
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• pp.79-89
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• 1992

The behavior of belt tension in OHC drive timing belt system was investigated analytically and experimentally for (1)fixed and (2)automatic tensioner. From the numerical results it was found that the automatic tensioner makes the belt tension larger than those of the fixed tensioner. When the initial belt tension decreased due to the belt elongation, the belt tension of the fixed tensioner could decrease to near zero while the belt tension for the automatic tensioner maintained above zero by the tensioner spring. The mean valve and the difference between the maximum and the minimum belt tension for the automatic tensioner increased compared with those of the fixed tensioner. Also, the numerical results for a hydraulic tensioner showed that the hydraulic tensioner has the good parts of both tensioners; i.e., thesmaller amplitude in belt tension and the higher mean tension. Experimental results for the automatic and fixed tensioner of the OHC timing belt system were in agreement with the theoretical results.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1155-1160
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• 2009

Poly(lactide) (PLA)-coated paperboards were prepared by solution coating and thermo-compression coating methods and their effect of coating on the packaging properties such as tensile, water resistance, water vapor barrier, and heat sealing properties was tested. Compared with uncoated control paperboard, tensile strength (TS) of PLA-coated paperboard increased profoundly (2.2-2.6 folds) with slight increase in elongation at break (E). Water absorptiveness (WA) of the paperboard decreased 74-170 folds and water vapor permeability (WVP) decreased 6.3-22.1 folds by coating with PLA, which indicates an increase in the hydrophobicity of the surface of paperboard. Compared with polyethylene (PE)-coated paperboard, both PLA-coated paperboard exhibited 2.3 time higher heat sealing strength. In addition, the PLA-coated paperboards showed equal or higher wet TS than PE-coated paperboard. All the test results showed that the paperboard coated by the thermo-compression coating method was similar to or better than those of coated by the solution coating method.

• Advances in materials Research
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• v.3 no.3
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• pp.129-137
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• 2014

Biocomposites from polypropylene (PP) and corn cob (CC) were investigated. The effect of corn cob content and maleic anhydride polypropylene (MAPP) as compatibilizer were studied. Results showed that addition of corn cob (CC) in PP have decreased the tensile strength and elongation at break, whereas modulus of elasticity of biocomposites increased. The biocomposites with the MAPP as compatibilizer exhibited higher tensile strength and modulus of elasticity compared biocomposites without MAPP. The morphology study of biocomposites indicates that enhanced the interfacial interaction and adhesion between filler and matrix with the presence of MAPP.

• Journal of Applied Reliability
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• v.7 no.4
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• pp.149-162
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• 2007

Field and accelerated tests are performed to assess the service life of construction sealants. Mathematical degradation models for tensile strength and elongation, that are the two major performance characteristics of sealants, are derived from the test results. Accelerated degradation test methods for assessing service life of construction sealants are developed based on the degrading performance and a numerical example is provided.

• Journal of the Korean Society of Safety
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• v.21 no.4 s.76
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• pp.55-59
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• 2006

The radiation effects on electrical and mechanical properties of LDPE/EVA blends with various vinyl acetate contents were investigated. Radiation degradation of LDPE/EVA blends were studied by using gelation, volume resistivity, permittivity, dissipation factor, elongation at break, and E-modulus. As vinyl acetate contents increased in LDPE/EVA blends, electrical insulation characteristics were deteriorated, but flexibility was improved. As irradiation doses increased, electrical insulation characteristics were improved, but flexibility was deteriorated.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.112-116
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• 2005

Composite films were prepared with soy protein isolate (SPI) and various clay minerals by casting from polymer and clay water suspension. Effects of clay minerals on film thickness, moisture content (MC), tensile strength (TS), elongation at break (E), water vapor permeability (WVP), and water solubility (WS) were tested. Properties including thickness, surface smoothness, and homogeneity of films prepared with organically modified montmorillonite (O-MMT), Wamok clay (W-clay), bentonite, talc powder, and zeolite were comparable to those of control SPI films. TS increased significantly (p<0.05) in films prepared with O-MMT and bentonite, while WVP decreased significantly (p<0.05) in bentonite-added films. WS of most nanocomposite films decreased significantly (p<0.05).

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.27-30
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• 1989

Lithium has been intercalated into $FeMoO_4Cl$, and deintercalated from $LixFeMoO_4Cl$ both electrochemically and chemically. The inserted $Li^+$ ions are stabilized in the distorted octahedral field in interlayer space of $FeMoO_4Cl$. The crystal symmetry is reduced from tetragonal to monoclinic due to the reduction of ferric to ferrous ions in $LixFeMoO_4Cl$ upon lithium intercalation. From the magnetic and structural data, it has been concluded that the high-spin electronic configuration of $Fe^{2+}(d_{xz}^2{d_{y2}^1}{d_1}{2d_z^12}{\cdot}_y2)$, corresponding to $^5E_g$, group term in $D_{4h}$ symmetry, can be stabilized by the elongation of $FeO_4Cl_{2-}$octahedra in a weak ligand field.

• Macromolecular Research
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• v.9 no.1
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• pp.30-36
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• 2001

Polybutadiene latex grafted (g-PB) in g-PB/SAN blends, i.e., acrylonitrile-butadiene-styrene terpolymer (ABS) were partially replaced by acrylonitrile-butadiene copolymer (NBR) with various acrylonitrile (AN) contents. Changes in morphology, physical and rheological properties were examined. The dispersed size of NBR was decreased as the miscibility with matrix SAM, was increased by increasing AN content in NBR upto 50 wt%. Impact strength was enhanced about two-fold due to the NBR dispersed with a slight larger size than the original g-PB. Gloss was effectively reduced as the particle size of NBR was increased. Tensile yield strength was decreased, and elongation at break or yield behavior at low shear rate were increased as g-PB was partially replaced by NBR having AN content less that 40 wt%.

• Journal of the Korean Society for Heat Treatment
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• v.6 no.3
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• pp.152-158
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• 1993

Effects of oxide film which is grown by heat treatment on the hydrogen embrittlement (HE) of 17-4 PH stainless steel were investigated. Specimems were tensile tested after cathodic hydrogen charging and the be haviors of HE were evaluated from the elongation change. It was found that specimems solution treated at $1040^{\circ}C$ for 1/2hour showed best retardation ability to HE for both aging conditions i.e. $480^{\circ}C{\times}1hr$ and $620^{\circ}C{\times}4hrs$. X-ray and Auger study revealed that the major composition of oxide films are $Cr_2O_3$ and $CuCr_2O_4$.