• 제목/요약/키워드: functional effect

검색결과 5,433건 처리시간 0.031초

A Comparison Study on Reinforcement Behaviors of Functional Fillers in Nitrile Rubber Composites

  • Seong, Yoonjae;Lee, Harim;Kim, Seonhong;Yun, Chang Hyun;Park, Changsin;Nah, Changwoon;Lee, Gi-Bbeum
    • Elastomers and Composites
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    • 제55권4호
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    • pp.306-313
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    • 2020
  • To investigate the reinforcing effects of functional fillers in nitrile rubber (NBR) materials, high-structure carbon black (HS45), coated calcium carbonate (C-CaCO3), silica (200MP), and multi-walled carbon nanotubes (MWCNTs) were used as functional filler, and carbon black (SRF) as a common filler were used for oil-resistant rubber. The curing and mechanical properties of HS45-, 200MP-, and MWCNT-filled NBR compounds were improved compared to those of the SRF-filled NBR compound. The reinforcing effect also increased with a decrease in the particle size of the fillers. The C-CaCO3-filled NBR compound exhibited no reinforcing effect with increasing filler concentration because of their large primary particle size (2 ㎛). The reinforcing behavior based on 100% modulus of the functional filler based NBR compounds was compared by using several predictive equation models. The reinforcing behavior of the C-CaCO3-filled NBR compound was in accordance with the Smallwood-Einstein equation whereas the 200MP- and MWCNT-filled NBR compounds fitted well with the modified Guth-Gold (m-Guth-Gold) equation. The SRF- and HS45-filled NBR compounds exhibited reinforcing behavior in accordance with the Guth-Gold and m-Guth-Gold equations, respectively, at a low filler content. However, the values of reinforcement parameter (100Mf/100Mu) of the SRF- and HS45-filled NBR compounds were higher than those determined by the predictive equation model at a high filler content. Because the chains of SRF composed of spherical filler particles are similarly changed to rod-like filler particles embedded in a rubber matrix and the reinforcement parameter rapidly increased with a high content of HS45, the higher-structured filler. The reinforcing effectiveness of the functional fillers was numerically evaluated on the basis of the effectiveness index (��SRF/��f) determined by the ratio of the volume fraction of the functional filler (��f) to that of the SRF filler (��SRF) at three unit of reinforcing parameter (100Mf/100Mu). On the basis of their effectiveness index, MWCNT-, 200MP-, and HS45-filled compounds showed higher reinforcing effectiveness of 420%, 70%, and 20% than that of SRF-filled compound, respectively whereas C-CaCO3-filled compound exhibited lower reinforcing effectiveness of -50% than that of SRF-filled compound.

운동과 신경가소성에 대한 고찰 (A Review of Exercise and Neural Plasticity)

  • 송주민
    • PNF and Movement
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    • 제6권2호
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    • pp.31-38
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    • 2008
  • Purpose: The purpose of this study were to overview the effect of exercise on neural plasticity and the proteins related to neural plasticity. Results: Exercise increased levels of BDNF(brain-derived neurotrophic factor), Insulin-like growth factor-I (IGF-I), Synapsin, Synaptophysin, VEGF(vascular endothelial growth factor) and other growth factors, stimulate neurogenesis, increase resistance to brain insult and improve learning and mental performance. These proteins improved synaptic plasticity by directly affecting synaptic structure and potentiating synaptic strength, and by strengthening the underlying systems that support plasticity including neurogenesis, metabolism and vascular function. Conclusion: Exercise-induced structural and functional change by these proteins can effect on functional movement, cognition in healthy and brain injured people and animals.

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The Biofeedback Scapular Stabilization Exercise in Stroke Patients Effect of Muscle Activity and Function of the Upper Extremity

  • Yang, Dae-Jung;Uhm, Yo-Han;Kim, Je-Ho
    • The Journal of Korean Physical Therapy
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    • 제27권5호
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    • pp.325-331
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    • 2015
  • Purpose: This study attempts to understand the effect of stabilization exercise of biofeedback scapular on muscle activity and functional evaluation of the upper extremity in stroke patients. Methods: Patients were divided into two groups; a biofeedback scapular stabilization exercise group comprised of 8 patients and a task-oriented training group including another 8 patients, and 30-minute exercise was performed 5 times a week for 8 weeks. Electromyogram was used to measure muscular activity of lower trapezius, deltoid middle, and serratus anterior. Fugl-Meyer Assessment and Manual Function Test were used to evaluate functions of the muscles mentioned. Results: Significant difference was observed in the comparison group before and after exercise in muscular activity of lower trapezius, deltoid middle, and serratus anterior, Fugl-Meyer Assessment, and Manual Function Test. Conclusion: Therefore, we could see that biofeedback scapular stabilization exercise is more effective than task-oriented training in facilitating muscle activation and functional capacity of upper limb.

산화그레핀을 이용한 바나듐레독스흐름전지용 카본펠트전극의 표면개질을 통한 전기화학적 활성개선 (Electrochemical Enhancement of Carbon Felt Electrode for Vanadium Redox Flow Battery with Grephene Oxide)

  • 이건주;김선회
    • 한국수소및신에너지학회논문집
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    • 제28권2호
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    • pp.206-211
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    • 2017
  • Carbon felt electrode for the vanadium redox-flow battery (VRFB) has been studied to see the effect of grephene oxide (GO) treatment on the surface of the carbon felt electrode. In this paper, surface of carbon felt electrodes were treated with various concentrations of grephene oxide. Electrochemical analysis, cyclic voltammetry (CV), was performed to investigate redox characteristics as electrode for VRFB. Also the effect of GO on the introduction of functional group on the surface of carbon felt electrodes were investigated using X-ray photoelectron spectroscopy (XPS), which discovered increase in the overall functional group content on the surface of carbon felts.

감마선 조사에 따른 참치 자숙액의 위생화 및 기능성 변화 연구 (Effect of Gamma Irradiation on the Microbial Safety and Biological Activities of Tuna Cooking Juices)

  • 변명우
    • KSBB Journal
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    • 제27권4호
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    • pp.222-226
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    • 2012
  • In this study, the effect of gamma irradiation on the microbial contamination and biological activities of tuna cooking juices was investigated. Tuna cooking juice was by-produced during the canning processing, and had various functional components. But, it was shown that the tuna cooking juice was seriously contaminated. Gamma irradiation effectively reduced the microbial population in tuna cooking juice. Also, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, tyrosinse inhibitory activity, and ACE inhibitory activity of tuna cooking juices were all increased as a result of gamma irradiation. These results suggest that wasted tuna cooking juices can be used as a functional component in the food and cosmetic industries if the irradiation technology were applied.

Sputtering에 의한 polyester 직물의 박막내구성 개선을 위한 수지처리 효과 (The Effect of Resin Treatment for Improving of the Metal Thin Membrane Fastness on Polyester Fabrics by Sputtering)

  • 구강;전상민;송병갑;박영미
    • 한국염색가공학회지
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    • 제18권3호
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    • pp.31-41
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    • 2006
  • Functional properties are available with sputtering. But sputtering treatment alone cannot got a good fastness performance to washing, rubbing and light. This research was objected to investigate optimum condition by sputtering on polyester through various processing conditions such as ion current and treatment time, and then various resin treated onto metal coated polyester fabrics in order to increase washing fastness of metal membrane. As the results, the optimum conditions revealed 1500 mA of ion current, 2 min of treatment time in sputter, and suitable resin concentrations were 2% of o.w.s (on the weight of solution) in resin treatment. Therefore, we could get enhanced anti-static effect and flex stiffness as well as washing fastness in sputtered polyester fabric with various resin treatment, for example, melamine and polyurethane.

The Performance Stability of Ophthalmic Material with UV-Block Effect Containing Hydroxyl Benzophenone Group and Tungsten Nanoparticles

  • Kim, Duck-Hyun;Sung, A-Young
    • 대한화학회지
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    • 제61권3호
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    • pp.97-103
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    • 2017
  • In this study, the functional hydrogel ophthalmic lens containing tungsten oxide nanoparticles, 2,4-dihydroxy benzophenone and 2-hydroxy-4-(methacryloyloxy) benzophenone were manufactured. HEMA (2-hydroxyethyl methacrylate), MMA (methyl methacrylate), AA(acrylic acid), the cross-linker EGDMA (ethylene glycol dimethacrylate), the initiator AIBN (azobisisobutyronitrile) and the functional additives including tungsten oxide nanoparticles, 2,4-dihydroxy benzophenone, and 2-hydroxy-4-(methacryloyloxy) benzophenone were used respectively. The measurements of water content and refractive index of the sample was decreased and increased, respectively. And also, the UV transmittance of produced lens containing 2,4-dihydroxy benzophenone, 2-hydroxy-4-(methacryloyloxy) benzophenone and tungsten oxide nanoparticles was measured. Based on the results of this study, it is judged that the performance improvement increased over time when 2-hydroxy-4-(methacryloyloxy) benzophenone was used as an additive, while the use of tungsten oxide nanoparticles influenced on blue-ray-blocking effect of the hydrophilic lens.

사회.문화적 환경이 모자의 변천에 미친 영향 -19세기 유럽을 중심으로- (A Effect of Sociocultural Environment on the Vicissitudes of Headgear -Focused on 19th Century in Europe-)

  • 김진구;임선희;김애련
    • 복식문화연구
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    • 제9권2호
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    • pp.295-307
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    • 2001
  • This study was investigated to a effect of sociocultural environment on the vicissitudes of headgear in Europe on 19th Century. Form of headgear was increasingly more functional and simple. It was needed various items with various usage. Since Industrial Revolution the french Revolution. A diffusion of sport and increase of leisure time gave rise to entrance of mass headgear with reasonability and simplicity. But female headgear was more decorative than males. Until late 19th century when female has participated in social performance, female headgear was not functional and simple form. More often female took male headgear(fedora, straw boater, cap, tc.) than bonnet when female role-awareness was changed and sport is diffused.

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참깨박에 함유된 Phytate와 Phenol 화합물의 제거가 단백질의 기능성에 미치는 영향 (Effect of Reduction of Phytate and Phenol Compound on the Functional Properties of Sesame Protein Concetrate)

  • 김진;박정룡
    • 동아시아식생활학회지
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    • 제3권2호
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    • pp.129-137
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    • 1993
  • This study was attempted to determine the effect of reduction of phytate and phenol compound on the functional properties of sesame protein concentrate. The concentrates were prepared by using dist-water, HCI and butanol. The content of phytate and phenol compound in defatted sesame meal were 4.55% and 3.42% respectively. Considerable amount of phytate was reduced by using HCI, and butanol was effective in removing phenol compounds, Higher bulk density and fat absorption were found in sesame protein concentrate prepared by butanol but higher water absorption was found in the concentrate prepared by dist-water. Also, emulsifying and foaming properties were improved by butanol treatment.

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볶음전 증자처리가 둥굴레 근경의 수용성 성분 및 갈색화에 미치는 영향 (Effect of Steaming Prior to Roasting of Polygonatum odoratum Roots on Its Water Solubles and Browning)

  • 권중호;임종호
    • 한국식품저장유통학회지
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    • 제4권2호
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    • pp.155-162
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    • 1997
  • This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.

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