• Textile Coloration and Finishing
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• 제9권4호
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• pp.7-19
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• 1997

The purpose of the study was to investigate the shrinkage and creep behavior of PET filaments which were prepared at various spinning speeds(3,300, 4,000, 5,000, 6,000, and 7,000m/min) and anneal($120^{\circ}$, 30min & $150^{\circ}$, 40min). In order to determine the shrinkage and creep behavior with the crystallinity change, PET filaments were treated with low(12$0^{\circ}C$, 30min) and high($150^{\circ}$, 40min) temperature conditions with hot air dryer under the constant tension. The results of the study were as follows: as the spinning speed increased, the degree of shrinkage and elongation of the sample treated by wet condition decreased. The sample with 0.01g/d of load under various spinning speeds showed shrinkage behavior and highest shrinkage ratio at $76^{\circ}$ which was Tg of PET. The degree of shrinkage and elongation of the treated sample was less than those of the untreated sample by wet treatment. Especially, there was less degree of shrinkage and elongation of the sample treated by higher temperature condition. In 3,300m/min of spinning speed the draw ratio of undrawn yarn of a mixture of a-axis orientation and c-axis orientation was 2.0, which is similar to the value of the traditional drawn yarn. Finally, there was a big range of shrinkage and elongation by wet treatment in 3,300 m/min of spinning speed.

• Biomolecules & Therapeutics
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• 제16권4호
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• pp.425-430
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• 2008

The objectives of this study were to prepare PLGA film onto the surface of the capsular tension ring (CTR) for controlled drug release and investigate the influence of plasticizers, the test drug and measurement conditions on flexibility of the film. Film solutions were prepared by dissolving PLGA, plasticizer (triethyl citrate, TEC or polyethylene glycol, PEG), test drug (dexamethasone) in ethyl acetate then films were prepared by spray coating and evaporation method. Then, the flexibility of PLGA film was determined by elongation test. The addition of plasticizer, PEG or TEC to PLGA copolymer caused a depression of glass transition temperature ($T_g$) and the elasticity of PLGA films increased. The addition of dexamethasone to the PLGA/TEC matrix decreased the flexibility of film. Dimensional factors of the PLGA films such as width and thickness were significantly influenced on flexibility of films and film length and elongation speed had no considerable influence on elongation of films. In this study, sufficiently flexible and stable PLGA films capable of being coated onto CTR could be prepared. This PLGA films can be used as a platform for local drug delivery.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제42권5호
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• pp.548-555
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• 1997

Sorghum seedlings lacking one of the phytochromes, phyB, have elongated internode, suggesting that they may have an alteration in gibberellin physiology. To test the possibility that phyB mutations affect seedling gibberellin perception and metabolism, the responsiveness of wild-type and phyB-1 seedlings to exogenous $GA_3$ was investigated. The phyB-1 showed higher internode elongation rate than the wild type in response to lower concentrations of exogenous $GA_3$ application, showing that the mutation causes an increase in responsiveness to GA. However, at the higher concentrations of $GA_3$ application, phyB-l and wild-type showed similar elongation rate, impling that responsiveness to higher concentrations of GA is not controlled by phytochrome. These results suggest that, although GAs are required for internode elongation, phyB does not act primarily by changing absolute levels of GAs but rather by decreasing seedling responsiveness to GAs at lower concentrations.

• Journal of the Korean Society for Heat Treatment
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• 제11권4호
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• pp.333-341
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• 1998

The study was investigated on the effect of austenitizing and austempering conditions on retained austenite amount and carbon contents in retained austenite and simultaneously the effect of these variation on hardness, tensile and impact properties. A material of as-cast condition is composed of bull's eye structure with ferrite surrounding spheroidized graphite having about $5-10{\mu}m$ size and matrix structure of pearlite. Then, the contents of spheroidized graphite was about 5%. The retained austenite and carbon contents in the retained austenite were increased with the increasing of austenitizing and austempering temperatures, while the retained austenite showed the peak value and is decreased with increasing of austempering time. With increasing of austenitizing temperature, tensile strength, elongation and impact absorb energy increased and hardness was almost not changed, while with increasing of austempering temperature, tensile strength and hardness decreased, whereas elongation and impact absorb energy was increased. With increasing of retained austenite amount, the tensile strength is slowly decreased but elongation was increased with direct proportion. Also, Impact absorb energy is shown identity value untile about 18%, but rapidly increased above it. Elongation and Impact absorb energy are strongly controlled by the amount of retained austenite, but tensile strength is affected with various factors such as retained austenite amount and bainitic morphology.

• Journal of the Korean Society for Heat Treatment
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• 제24권3호
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• pp.133-139
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• 2011

This study has been investigated for tensile properties with lead-free brass containing 1 wt.% of Bi. And also characteristic of corrosion resistance was analyzed by polarization test. An increase of tempering temperature was found to tend to decrease tensile strength, and percentage of elongation was shown to be the lowest value at $300^{\circ}C$. On the other hand, the elongation was increased with an increase of tempering temperature after $300^{\circ}C$. The change of mechanical properties was closely related with the content and shape of acicular Witmanst$\ddot{a}$tten ${\alpha}$ formed at the interface of ${\beta}$ phase as well as in ${\beta}$ phase. Tensile strength had a tendency to be decreased with an increase of test temperature. The elongation was shown to be the lowest value at around $300^{\circ}C$, while it began to increase as test temperature rose after $300^{\circ}C$. It might be speculated that the reason that elongation was decreased was found to form bismuth film at the interface of ${\alpha}/{\beta}$ phase leading to be easily brittle when loaded by tensile stress. The lead-free brass containing 1 wt.% of Bi had similar characteristic of corrosion resistance with a free-cutting brass with 3.4 wt. % of Pb in spite of higher fraction of ${\beta}$ phase.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• 제46권3호
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• pp.257-264
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• 2010

In order to improve the breaking strength and elongation of Polybutylene succinate (PBS) monofilament, the monofilament was produced by blending PBS and Polybutlyne adipate-co-terephthalate (PBAT). The PBS/PBAT blend monofilament was prepared by the melt spinning system, and the weight ratios of the compositions of PBS/PBAT was 100/0, 95/5, 90/10 and 85/15, respectively. The breaking strength, elongation, softness and crystallization of PBS/PBAT blend monofilament were analyzed by using a tensionmeter, softness measurement, X-ray diffractometer in the both dry and wet conditions. The PBS/PBAT blend monofilaments were spun in the take-up velocity of 1.19m/sec under the drawing ratio of 6.8:1 condition. The production volumes of PBS/PBAT blend monofilaments showed 20% less than that of Nylon. The breaking strength of PBS/PBAT blend monofilaments were decreased as PBAT contents increased, while elongation and softness were increased. In case of PBAT content were over 5%, the breaking strength, elongation and softness of PBS/PBAT blend monofilaments were not shown to increase in spite of increasing in PBAT contents. Based on these results, it was possible to make the monofilaments with the maximized physical properties when the PBAT contents at 5%.

• Polymer(Korea)
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• 제26권4호
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• pp.468-476
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• 2002

Oxy-PAN fiber prepared from the preoxidation and saponification of raw PAN fiber is known to elongate and contract when immersed in basic and acidic solutions, respectively. In this study, about 30% elongation in NaOH solution and 30∼50% contraction in HCl solution have been observed. In mechanical test, the mechanical properties of oxy-PAN fiber in the contracted state was stronger than that in the elongated state. These behaviors and mechanical properties are compared to those of living muscle and linear actuator. The change of length in NaOH and HCl solutions is due to switching between a hydrophilic and a hydrophobic structure. Other reasons are exchange of ion and water in/out of oxy-PAN fiber, and osmotic pressure difference associated with relevant ions. Much studies are needed to clarify the effective factors on but the oxy-PAN fiber's elongation/contraction behavior and mechanical properties, but the oxy-PAN fiber perpared in our laboratory has a sufficient potential for application as artificial muscle and linear actuator.

• Journal of Ocean Engineering and Technology
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• 제23권4호
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• pp.52-57
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• 2009

The effect of aging treatment on the microstructure and mechanical properties of super duplex stainless steel with W was investigated. The phase was precipitated mainly at the early stage of aging and a lower aging temperature under $750^{\circ}C$, but the phase was formed after long-term aging treatment between $600^{\circ}C$ and $900^{\circ}C$. The volume fraction of the phase increased with aging temperature up to $750^{\circ}C$ and then decreased up to $900^{\circ}C$. With an increase in the aging time, the volume fraction phase at the early stage of aging increased slightly, and then increased rapidly beyond a certain time. The rapid increase in the tensile strength and hardness and decrease in the elongation and impact toughness were measured with aging temperatures up to $750^{\circ}C$. On the other hand, the tensile strength and hardness decreased slightly, and the elongation and Charpy impact toughness were unchanged with aging temperatures over $750^{\circ}C$. The tensile strength and hardness increased rapidly at the early stage of aging, and then increased slowly beyond a certain time. The elongation and Charpy impact toughness decreased rapidly at the early stage of aging, and then remained unchanged beyond a certain time. The phase that formed at the early stage of aging and the lower aging temperature had a considerable effect on the elongation and Charpy impact toughness of the super duplex stainless steel with W.

• Science of Emotion and Sensibility
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• 제19권2호
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• pp.19-26
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• 2016

Previous research has shown that people perceive the larger volume for tall and lean cylindrical containers over short and wide containers of the same volume (e.g., Raghubir & Krishna, 1999; Wansink & Van Ittersum, 2003). The present research demonstrated that this elongation effect is reversed for boxes, presumably due to the affordance of the boxes. Two studies showed that participants judge short and wide boxes as having larger volume than long and lean boxes of the same volume. This effect replicated through two types of presentation formats (drawing, Study1; actual object, Study2) when the choice between two boxes was forced (Study 1) and not (Study 2). The results also replicated among participants residing in the U.S. (Study 1) and participants residing in Korea (Study 2). The reversed elongation effect held for liquid materials in general (water, Study 1; drinks, Study 2). Theoretical and managerial implications are discussed.

• Journal of the Korean Society of Clothing and Textiles
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• 제21권4호
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• pp.710-717
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• 1997

An investigation made of fabric strength & elongation and the lock stitch seam strength & elongation by stitch density (N1.5; 26 stitches/3 cm, N2.0; 19 stitches/3 cm, N2.5; 14 stitches/3cm) depending on methods of. sample prepariation (angle variations of unseamed sample and overlapping way of seamed sample) It found maximum stitch density that results of the seam strength test was highist in each angle of bias. The results obstained were as follows: 1. As the results of fabric strength and elongation tests as a function of angle of bias, breaking strength were that warp and weft angles (0$^{\circ}$, 90$^{\circ}$) were much higher than bias angles (20$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$, 60$^{\circ}$) . And otherwise breaking elongation were that 45$^{\circ}$ angle of bias were highest and were that the warp & weft way were lower. 2. As the results of the seam strength tests by the stitch density under samples of same angles, the maximum stitch density were those; under 0$^{\circ}$/0$^{\circ}$, 60$^{\circ}$/60$^{\circ}$:F1, F2-N2.0, F3-N1.5, under 20$^{\circ}$/20$^{\circ}$, 30$^{\circ}$/30$^{\circ}$, 45$^{\circ}$/45$^{\circ}$: F1-N2.5, F2-N2.0, F3-N1.5, under 90$^{\circ}$/90$^{\circ}$: F1, F2, F3-N1.5. 3. As the results of the seam strength tests by the stitch density under samples of symmetry angles, the maximum stitch density were those; under 20$^{\circ}$/-20$^{\circ}$, 30$^{\circ}$/-30$^{\circ}$, 60$^{\circ}$/-60$^{\circ}$: F1, F3-N1.5, F2-N2.0, under 45$^{\circ}$/-45$^{\circ}$: F1, F2-N2.0, F3-N1.5.