• Title/Summary/Keyword: tensile breaking

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Study on the Effects of Single Fiber Tensile Properties on Bundle Tensile Properties through Estimation of HVI Bundle Modulus and Toughness

  • Koo, Hyun-Jin;Jeong, Sung Hoon;Suh, Moon W.
    • Fibers and Polymers
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    • v.2 no.1
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    • pp.144-147
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    • 2001
  • The HVI properites and Mantis single fiber tensile properties were analyzed to evaluate the relationship between fiber and bundle tensile properties. For this study, a new method has been developed for estimating the modulus and toughness of cotton fiber bundles directly from the HVI tenacity-elongation curves. The single fiber tensile properties were shown to be translated well into the bundle tensile properties. The single fiber breaking elongation was found to be the most significant contributing factor to bundle tensile properties. The bundle breaking elongation and toughness were shown to increase as the single fiber breaking elongation increased. The bundle modulus increased as the single fiber breaking elongation and/or standard deviation of single fiber breaking elongation decreased.

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Experimental Study on Ultimate Tensile Failure Properties of Laminated Rubber Bearings (적층고무받침의 극한인장파괴 특성에 관한 실험적 연구)

  • Oh, Ju;Jung, Hie-Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.4A
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    • pp.303-309
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    • 2011
  • Laminated rubber bearing is the most commonly used device for seismic base isolation of bridge structures. It is important to know performance and behavior characteristics of the laminated rubber bearings. The main evaluation factors of the rubber bearing are classified as compressive, shear and tensile behavior characteristics. The reference data of compressive and shear characteristics are rich, but the reference data of tensile characteristics is scarce. In this study, tensile test results of the rubber bearing with variation of shape factor and shear deformation are investigated for mechanical property. When tensile deformation in normal condition is increasing, tensile cycle behavior curve becomes non-linear and tensile breaking point is 300%. On the other hand, tensile breaking point is shear deformation condition is about 40%. Furthermore, when shape factor is lower, tensile breaking point is decrease. This results mean that tensile breaking point is decreased in triaxial tensile deformation because of cracks caused by internal void of the rubber bearings. This experimental data can be used as the reference data of tensile characteristics for designing seismic isolation of structures.

The Mechanical Appearances and Microscopic Tissue Reactions of the Suture Materials in vivo (생체내 이식된 흡수성 봉합사들의 물리적 성질 변화와 조직 소견에 관한 연구)

  • 김남중;김명철
    • Journal of Veterinary Clinics
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    • v.13 no.2
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    • pp.184-194
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    • 1996
  • A comparative study of three absorbable suture materials of chromic catgut, Dexon II (a polyglycolic acid suture with a polycaprolate coating system) and Coated Vicryl (a polyglactin 910 suture with a glycolide-lactide-calcium stearate coating system) was undertaken in terms of tensile strength, breaking elongation, appearances of the suture materials in the subcutaneous layer of rats and of tissue reaction in the intramuscular layer of rats. The initial tensile strength of chromic catgut and the tensile strength after 21 days were about 1.55 kg and 0.19 kg, respectively. Those of Dexon II were about 2.01 kg and 0. 20 kg, respectively. Those of Coated Vicryl were about 2.39 kg and 0.48 kg, respectively. Coated Vicryl showed the highest tensile strength among the three materials during the whole period. On the other hand, Dexon II showed the highest breaking elongation among the three materials during the first week. But the breaking elongation of Dexon II rapidly continuously decreased during the whole period. The appearances of the suture materials in the subcutaneous layer of rats showed that chromic catgut was the fastest among the three materials, whereas it formed comparatively much connective tissue. The intramuscular absorption rate and tissue reaction of Dexon II were similar to those of Coated Vicryl. The intramuscular absorption rate of these was fairly late when compared with chromic catgut. And the tissue reaction appearance of these showed the formation of a granuloma with foreign body giant cells, macrothages and epitheloid cells by the 28th day in the experimental period.

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Relationship between Degree of Grain Shedding and Histological Peculiarities of Abcission Region of Red Rice(Oryza sativa L.) Collected in Korea (국내 자생벼 계통의 탈립성과 이층조직의 특성)

  • 임원재;최광귀;진일두
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.3
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    • pp.239-247
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    • 1990
  • In order to investigate the degree of grain shedding of red rices collected in Korea, breaking tensile and breaking bending strengths of 269 varieties; 82 Korean and 100 foreign red rices and 87 Korean cultivars including 26 native varieties, 30 Japonica-Indica hybrids and 31 Japonica type varieties, were measured at harvest time. Also, histological characteristics of abscission region between spikelet and pedicel were observed. The breaking tensile and breaking bending strengths of both Korean and foreign red rices were weaker than those of Japonica-Indica hybrids which were known as easily shedding varieties in Korea. Abscission layers were observed in the majority of Korean red rices except for 5 varieties, and those of all varieties belonging to both long grain types and 'Sare's were cracked completely at harvest time, while those of round grain types were not cracked except one variety. The breaking tensile and breaking bending strengths of the tested varieties having cracked abscission layer were weaker than those of non-cracked ones. Both strengths of breaking tensile and breaking bending were positively correlated with diameter of supporting zone and thickness of sclerenchyma tissue surrounding central vascular tissue of suporting zone at 0.1% significant level, respectively.

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The Combined Tensile and Torsional Behavior of Irregular Fibers

  • He, Weiyu;Wang, Xungai
    • Fibers and Polymers
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    • v.3 no.1
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    • pp.31-37
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    • 2002
  • Most fibers are irregular, and they are often subjected to combined loading conditions during processing and enduse. In this paper polyester and wool fibers under the combined tensile and torsional loads have been studied for the first time using the finite element method (FEM). The dimensional irregularities of these fibers are simulated with sine waves of different magnitude and frequency. The breaking load and breaking extension of the fibers at different twist or torsion levels are then calculated from the finite element model. The results indicate that twist and level of fiber irregularity have a major impact on the mechanical properties of the fiber and the effect of the frequency of irregularity is relatively small.

Reological Studies on Cocoon Filament II. Changes of strength and elongation at breaking related to the stretching speed and swelling degree (견사의 탄성적성질에 관한 연구 II. 인장속도 및 팽윤에 따른 파괴강신도의 변화)

  • 남중희
    • Journal of Sericultural and Entomological Science
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    • v.14 no.2
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    • pp.105-112
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    • 1972
  • The effects of the stretching speed and the swelling degree of cocoon filaments on load-elongation curve were tested by tensilon with special attachments. The values of breaking strength, elongation at break and initial tensile strength obtained from load elongation curves are summarized as follows; 1. The breaking strength of the swollen cocoon filament appeared to increase at the high stretching speed, while elongation at break decreased. 2. Load-elongation curve became crinkled at the low speed of stretching. It suggests that both slip and break of the macrofibrils may occur in swelling of cocoon bave. 3. Breaking strength appeared to considerably decrease and elongation at break not to increase in swelling test at 9$0^{\circ}C$ for 60 min. 4. The initial tensile strength was influenced by the stretching speed and swelling degree of cocoon filaments.

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A Study on the Mechanical Change of Emulsion-Treated Hair by Color

  • Ko, Hee-Ja;Park, Jang-Soon
    • Textile Coloration and Finishing
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    • v.34 no.2
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    • pp.127-133
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    • 2022
  • With the increasing interest in the expression of individuality and appearance of modern people, it is time to conduct research and development of novel hair coloring from various angles. Therefore, taking into account the order of discoloration of hair pigments, we selected a creative and novel emulsion as a novel material for hair coloring, rather than a cosmetic material such as hot water extract using natural products dealt with in previous studies, commercially available hair manicure, and oxidation hair dye for hair. Thus, the change in tensile strength and elongation of hair samples by color was studied. As a result of the study, hair with green emulsion paint had a significantly higher maximum load, maximum stress, maximum elongation and breaking load, breaking stress, breaking elongation values are shown. Maximum in terms of modulus, green emulsion applied hair and the control group were higher in the 0-15s strain and 15-145s sections, respectively, and the tangential modulus value was much higher in the control group than the experimental group hairs in all the 0-145s sections. This study, which analyzes the dynamic changes of hair samples that extend the daily color gamut, will greatly contribute to the development of innovative hair coloring materials in the research and production of hair beauty works, and it is judged that it will also contribute to the development of the beauty industry.

A Study on Tensile Property of MMT (Montmorillonite) Reinforced Chopped Strand Glass Fiber/Vinylester Composites (MMT(Montmorillonite)를 적용한 Chopped Strand Glass Fiber-Vinylester 복합재의 인장특성 연구)

  • Jung, Yong-Hwa;Ku, Ja-Ho;Lee, Wi-Ro;Rhee, Kyong-Yop
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.4
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    • pp.619-624
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    • 2012
  • In this study, MMT/fiber/polymer composites were fabricated by impregnating chopped strand glass mat into a vinylester resin mixed with clay. Tensile tests has been performed by using a universal testing machine to determine the effect of MMT addition on the tensile properties of MMT/chopped strand glass fiber/vinylester composites. And some pictures which are magnified cross section of breaking parts are has been taken by using a FE-SEM to confirm the behavior at breaking. The contents ratio of MMT applied in the composites were 0.5, 1.0, 1.5, and 2.0 wt% respectively. It has been found that the tensile strength and elastic modulus of MMT/chopped strand glass fiber/vinylester composites were improved at a proper content of MMT. Tensile strength and elastic modulus were maximized at a content of 1.0 wt% due to most effective dispersion of MMT. On the contrary, the failure strain was increased as MMT content was increased.

Polymerization and Preparation of Functional Ophthalmic Material Containing Carbon Nanoparticles

  • Lee, Min-Jae;Sung, A-Young
    • Korean Journal of Materials Research
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    • v.28 no.8
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    • pp.452-458
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    • 2018
  • This research is conducted to create a functional hydrogel ophthalmic lens containing nanoparticles. Carbon nanoparticles and PEGMEMA are used as additives for the basic combination of HEMA, MA, and MMA, and the materials are copolymerized with EGDMA as the cross-linking agent and AIBN as the thermal initiator. The hydrogel lens is produced using a cast-mold method, and the materials are thermally polymerized at $100^{\circ}C$ for an hour. The polymerized lens sample is hydrated in a 0.9 % saline solution for 24 hours before the optical and physical characteristics of the lens are measured. The refractive index, water content, contact angle, light transmittance, and tensile strength are measured to evaluate the physical and optical characteristics of the hydrogel lens. The refractive index, water content, contact angle, UV-B light transmittance, UV-A light transmittance, visible light transmittance, tensile strength and breaking strength of the hydrogel lens polymer are 1.4019~1.4281, 43.05~51.18 %, $31.95{\sim}68.61^{\circ}$, 21.69~58.11 %, 35.59~84.26 %, 45.85~88.06 %, 0.1075~0.1649 kgf and 0.1520~0.2250 kgf, respectively. The results demonstrate an increase in refractive index, tensile strength and breaking strength and a decrease in contact angle and light transmittance. Furthermore, the visible light transmissibility is significantly increased at PEG 10 %. It is clear that this material can be used for high-performance ophthalmic lenses with wettability, ultraviolet ray blocking effect, and tensile strength.

Reological Studies on Cocoon Filament. 1. Tensile Properties of Filament by the Portion of Cocoon Layer (견사의 탄성적성질에 관한 연구 1. 견층부위별견사의 항장성)

  • 남중희
    • Journal of Sericultural and Entomological Science
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    • v.14 no.1
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    • pp.43-47
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    • 1972
  • The tensile properties of cocoon filament obtained from the dried cocoon were studied by deniroscope and tensilon with special attachments. The strength and dried elongation at break feint with dry and swollen samples were observed. The apparent young's modulus was also calculated with the dry samples. The results obtained are as follows. 1) The breaking strength of dry and swollen samples decreased in parallel with denier decreasing ratio in the whole length of a cocoon filament. 2) Tensile strength of inner-layer filament, when treated at the temperature of 95$^{\circ}C$ for 15 min., was 37 per cent of outer-layer filament. 3) By swelling treatment, the breaking strength of the filament was decreased but the elongation was increased. 4) Apparent young's modulus and tensile strength per denier of inner-layer filament were higher than those of the rest cocoon layer.

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