• Title/Summary/Keyword: elongation control

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Effects of Silica-Silane for CIIR Vibration Isolation Compound upon Increased Mechanical Properties (실리카-실란이 클로로부틸 방진고무 복합소재의 기계적 물성 증가에 미치는 영향)

  • Kim, Sung Min;Kim, Kwang-Jea
    • Polymer(Korea)
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    • v.39 no.1
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    • pp.107-113
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    • 2015
  • The effects of silica-silane in CIIR vibration isolation compound were investigated regarding mechanical and dynamic properties. Addition of silica-silane in the compound resulted in higher tear resistance strength and elongation at break than the control, which was increased by 13% and 14%, respectively. Other values such as tensile strength and hardness did not show significant changes. Viscoelastic property results supported that the improvement of tear resistance strength and elongation at break resulted from the formation of 3-dimensional network structure between silica and CIIR. The mechanism of the tear resistance strength and elongation at break improvement was discussed.

Development of Alloy with High Strength and Damping Capacity for High-Performance of Precision Devices by Vibration Control (진동제어에 의한 정밀기기의 고성능화를 위한 고강도 및 고감쇠능 합금개발)

  • Kana, Chang-Yong;Kim, Ik-Su
    • Journal of Ocean Engineering and Technology
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    • v.22 no.6
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    • pp.46-51
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    • 2008
  • The effect of the addition of Co and N and subzero treatment on tensile strength and damping capacity was investigated in Fe-Cr-Mn alloy. Austenite was transformed into martensite by cold rollins increasing the degree of cold rollins led to an increase in the volume fraction of martensite. The damping capacity linearly increased with increasing volume fraction of ${\varepsilon}$ martensite in cold rolled specimens and subzero treated specimens after cold rolling. The volume fraction of ${\varepsilon}$ martensite, tensile strength and damping capacity was also increased by the addition of Co, while this treatment decreased the elongation. However, the volume fraction of ${\varepsilon}$ martensite, elongation and damping capacity were reduced by the addition of N, although the tensile strength increased. Tensile strength and damping capacity werealso increased by subzero treatment, while elongation decreased.

A Study on Physical Properties of Hair according to Repeated Hair Manicure Treatment (헤어 매니큐어 반복시술에 따른 모발의 물성변화)

  • Kim, Ok-Jun;Kim, Sun-Ah
    • Fashion & Textile Research Journal
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    • v.10 no.2
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    • pp.236-241
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    • 2008
  • Hair manicure is usually and widely operated in the area of hair-dyeing by the reason that acidic hair color is less damaged and more stable than other chemical color treatment. However, there is no an in-depth study to prove them. This study purposes to provide basic resources for effectively using products of hair manicure by experiments on Physical Properties of Hair. Hair of one healthy woman in mid-20's, Level 4, was sampled for experiments. For the tests, hair samples were classified by the frequency of hair manicure treatment The control group(a), once treatment(b), twice(c), three times(d), four times(e) and five times(f). The results were measured with Scanning Electron Microscopy(SEM) and Tensile Strength and Elongation test. The lower Values of Tensile Strength according to repeated hair manicure treatment. Elongation is not affected by the frequency of hair manicure treatment. There was no remarkable change of hair surface in once(b) and twice(c) treatment. The change of hair surface which was able to judge by cuticle layers looseness, tunics and the transformation of cuticle cell were observed in the hair samples operating more than three times(d) of hair manicure treatment.

Structure of a single polymer chain confined in a dense array of nanoposts

  • Joo, Heesun;Kim, Jun soo
    • Proceeding of EDISON Challenge
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    • 2015.03a
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    • pp.48-52
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    • 2015
  • Control of polymer conformations in heterogeneous confinement plays an important role in natural and engineering processes. We present a simulation study on the conformational structure and dynamics of a single, flexible polymer in a dense array of nanoposts with different sizes and separations, especially, when the volume of the interstitial space formed between four nanoposts is less than the size of the polymer chain. When a polymer is placed in the array of nanoposts, the size of polymer increases compared with that in the absence of nanoposts due to the confinement effect. It is shown that when a polymer is confined in the array of nanoposts the chain is elongated in the direction parallel to the nanoposts. As the interstitial volume between four nanoposts decreases either by increasing the nanopost diameter or by decreasing the separation between nanoposts, the chain elongation becomes more pronounced. On the contrary, the polymer size varies in a non-monotonic fashion, with an initial elongation followed by a chain contraction, as the interstitial volume is reduced both by increasing the nanopost diameter and decreasing the separation at the same time while keeping constant the width of the passageway between two nanoposts. The simulation analysis shows that the non-monotonic dependence of polymer size is determined by interplay between the chain alignment along the nanoposts in each interstitial volume and the chain spreading through passageways over several interstitial volume.

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MECHANICAL PROPERTIES OF TITANIUM CONNECTORS TREATED BY VARIOUS WELDING TECHNIQUES (용접방법에 의한 타이타늄 연결부의 기계적 성질에 관한 연구)

  • Lee, Soo-Young;Chang, Ik-Tae;Heo, Seong-Joo;Yim, Soon-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.37 no.5
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    • pp.545-566
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    • 1999
  • The use of pure titanium and titanium alloys have been increased recently in fixed, removable prosthodontics and implant fields as a framework. But when they were used for superstructures of implant or metal framework of removable prosthesis, welding is necessary to reconnect the fracture site to control the casting distortions. To overcome the difficulties in soldering the titanium due to high oxidation property, much effort have been devoted. In this study, some of mechanical properties were compared between pure titanium and Ti-6Al-4V alloy by using after welding, electron beam welding technique and tungsten arc welding. Mechanical properties such as tensile strength, yield strength, elongation and microhardness were measured. And, in order to compare the effect of welding site and surrounding metal tissue according to the welding condition, SEM photographs were taken and element distribution was observed by Wave Dispersion Spectroscopy. Through analyses of the data, following results were obtained; 1. In items such as tensile strength, yield strength and elongation according to the welding techniques of pure titanium, only tungsten arc welded group showed significant lower value than other groups(P<0.05). 2. In items such as tensile strength and yield strength according to the welding techniques of Ti-6Al-4V alloy, control group and tungsten arc welded group showed significant difference among all the groups(P<0.05). 3. Ti-6Al-4V alloy exhibited significantly greater elongation than control group when the laser welding method and electron beam welding method were used, and elongation showed increasing tendency. 4. Pure titanium specimens exhibited increasing tendency of microhardness regardless of the weld-ing technique applied, and especially tungsten arc welded group demonstrated a great increase of microhardness than parent metal. 5. There was no hardness change in laser welded group and electron beam welded group of Ti-6Al-4V alloy, but in tungsten arc welded group, hardness changed greatly from parent metal to weld seam. 6. Through the metallographic examination and scanning electron microscopy, laser welding caused central fusion and recristallizations were formed and tungsten arc welding caused localized fusion to 0.3-0.7mm from the surface.

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Effect of UV-B Radiation on the Leaf Growth of Rice Seedling (벼 유묘의 엽생장에 대한 자외선의 효과)

  • Sung, Jwa-Kyung;Lee, Su-Yeon;Kim, Tae-Wan;Hwang, Seon-Woong;Park, Moon-Hee;Song, Beom-Heon
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.1
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    • pp.25-30
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    • 2004
  • Rice seedlings were used to examine the effect of UV-B radiation on leaf elongation and development. Leaf elongation in both rice seedlings showed differently depending on each leaf age. UV-B radiation strongly reduced leaf elongation, 58-66% compared to without UV-B radiation, of two rice seedlings, therefore, those seedlings could not grow further. Both control and plants grown under UV-B regime showed a diurnial fluctuation in growth rate, showing maximum growth during the light period and minimum during the dark period. Leaf growth at the third leaf stage by UV-B treatment was considerably reduced by 1.7-fold than the control whereas at the fifth leaf stage was not changed. Hydrogen peroxide was considerably increased in the second phase of UV-B-induced response as catalase and peroxidase are deactivated with an increase of UV-B radiation.

Effect on Plant Growth, Fruit Elongation and Quality by Rootstock Sort of Oriental Melon (Cucumis melo L. var. makuwa Makino) (대목의 종류가 참외의 생장, 과실비대 및 품질 미치는 영향)

  • Shin, Yong-Seub;Seo, Young-Jin;Yeon, Il-Kweon;Do, Han-Woo;Lee, Ji-Eun;Choi, Chung-Don;Park, So-Deuk;Kim, Byung-Soo
    • Journal of Bio-Environment Control
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    • v.15 no.4
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    • pp.358-363
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    • 2006
  • Results on growth and fruit elongation and quality by rootstock sort of oriental melon were followed; Growth of upper part of oriental melon was faster grafted seedlings than self-root seedlings and among grafted seedlings, Elite and Shintozoa rootstocks were better than Hongtozoa. Growth of Elite and Shintozoa rootstocks, stem length and leaf number, were laster after 30 days of seedling transplant. Fruit elongation had no difference in rootstocks sort. Fruit weight was higher Elite and Shintozoa grafted seedlings than self-root seedlings but soluble solid contents of fruit was higher self root seedlings, $13.9^{\circ}Brix$, than Elite grafted seedlings, $12.5^{\circ}Brix$.

A Study on the Development of Traditional Korean Paper Changphanji by the Bast Fiber of Paper Mulberry (닥나무의 인피섬유(靭皮纖維)를 이용(利用)한 전통(傳統) 한지장판지(韓紙壯版紙) 개발(開發)에 관(關)한 연구(硏究))

  • Cheon, Cheol
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.4
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    • pp.53-64
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    • 1990
  • This study was carried out to develop the traditional korean paper changphanji from the bast fiber of paper mulberry The results obtained were as follows: 1. The variations in the basis weight were remarkable, but there were no significant adverse effects on the tensile strength and thickness. 2. The stamping have contributed to the improvement of smoothness and the control of thickness. The automatic pressing system recommended to obtain good control of thickness. 3. The average density of the traditional korean paper changphanji was 1.06g/$cm^3$. 4. The changphanji developed in this study gave a clude, but excellent toughness and warm feeling. Some fiber lumps, dark spots and bamboo, screen marks were also obserded. 5. The tensile strength of four-fold sheet changphanji is highest and those of two-fold sheet changphanji is lowest. the lengthwise tensile strength was higher than crosswise one due to the fiber. 6. The elongation of three-fold sheet changphanji was highest 7. The water absorption of all products ranged from 11.3g/$m^2$ to 17.5g/$m^2$. 8. The wight loss by abrasion was 34.0%(four-fold sheet) 31.6%(three fold sheet), 31.0% (two-fold sheet)respectively. 9. Based on the results obtained. tensile strength and elongation, the four-fold sheet was excellent. the use of the bast fiber of paper mulberry as a raw material is attractive point which can not obtained from the commercial changphanji made from other raw materials.

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Effects of TPA and IAA on Corn Coleoptile Elongation (옥수수 자엽초의 신장에 미치는 TPA와 IAA의 효과)

  • 정은수
    • Journal of Plant Biology
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    • v.35 no.1
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    • pp.77-84
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    • 1992
  • In view of the well-established role of protein kinase C effector element in signal transduction of animal systems, the possibility of diacylglycerol (DAG) and its analog 12-O-tetradecanoylphorbol13-acetate (TPA) having an effect on auxin-induced growih of com coleoptiles was explored. Both DAG and TP A were found to promote cell elongation in the coleoptile tissue_ Treatment of tissue with these protein kinase C-activating agents resulted in increase in the growth rate over the control by about 300%. When 1M was applied to TPA-pretreated coleoptiles. auxin effect appeared synergistic. Morever. coleoptile growth was found to be inhibited by staurosporine and methylated TPA, both of which are known to specifically inhibit protein kinase C. Electrophoretic and autoradiographic patterns of soluble proteins from the coeoptiles indicated that either 1M or TPA tereatment resulted in increased phosphorylation of certain proteins of 205 Kd. 66 Kd and 32 Kd in size. The results obtained from the present work suggest that protein kinase C may be associated with auxin action on cell elongation in the corn coleoptile segments.gments.

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Anti-Oomycete Activity and Pepper Root Colonization of Pseudomonas plecoglossicida YJR13 and Pseudomonas putida YJR92 against Phytophthora capsici

  • Elena, Volynchikova;Ki Deok, Kim
    • The Plant Pathology Journal
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    • v.39 no.1
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    • pp.123-135
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    • 2023
  • Previously, Pseudomonas plecoglossicida YJR13 and Pseudomonas putida YJR92 from a sequential screening procedure were proven to effectively control Phytophthora blight caused by Phytophthora capsici. In this study, we further investigated the anti-oomycete activities of these strains against mycelial growth, zoospore germination, and germ tube elongation of P. capsici. We also investigated root colonization ability of the bacterial strains in square dishes, including cell motility (swimming and swarming motilities) and biofilm formation. Both strains significantly inhibited mycelial growth in liquid and solid V8 juice media and M9 minimal media, zoospore germination, and germ tube elongation compared with Bacillus vallismortis EXTN-1 (positive biocontrol strain), Sphingomonas aquatilis KU408 (negative biocontrol strain), and MgSO4 solution (untreated control). In diluted (nutrient-deficient) V8 juice broth, the tested strain populations were maintained at >108 cells/ml, simultaneously providing mycelial inhibitory activity. Additionally, these strains colonized pepper roots at a 106 cells/ml concentration for 7 days. The root colonization of the strains was supported by strong swimming and swarming activities, biofilm formation, and chemotactic activity towards exudate components (amino acids, organic acids, and sugars) of pepper roots. Collectively, these results suggest that strains YJR13 and YJR92 can effectively suppress Phytophthora blight of pepper through direct anti-oomycete activities against mycelial growth, zoospore germination and germ tube elongation. Bacterial colonization of pepper roots may be mediated by cell motility and biofilm formation together with chemotaxis to root exudates.