• Elastomers and Composites
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• 제31권4호
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• pp.292-297
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• 1996

• Elastomers and Composites
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• 제30권1호
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• pp.42-49
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• 1995

• 한국정밀공학회지
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• 제24권2호
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• pp.41-46
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• 2007

Recently, the study for filling imbalance in thermoplastic polymer has gradually been increased. However, it is hard to find the researches for filling imbalance of thermoplastic elastomer(TPE). The experiment of filling imbalance was conducted for the three kinds of thermoplastic vulcanizes(TPVs) in the mold with geometrically balanced runner system. In this experiment, the effects of the melt temperature and injection speed on the filling imbalance were investigated. To solve the filling imbalance, Runner Core pin(RC pin) in the experimental mold was adopted and it's effects was tested. In this paper, we present that the insert length of RC pin is dependent to each polymers for optimal filling balance.

• Elastomers and Composites
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• 제50권4호
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• pp.245-250
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• 2015

Recycling of ethylene-propylene-diene terpolymer (EPDM) scrap was tried by blending with polypropylene (PP). EPDM scrap powder was prepared by shear pulverization process at high temperature, which may lead to selective chain scission induced by difference in the critical elastic coefficient. On the other hand, EPDM scrap powder was prepared by adding a selected reclaiming agent during shear pulverization process at high temperature. Terpene as a bonding agent was then introduced to improve adhesion property. PP, used as a matrix for manufacturing thermoplastic elastomer, was modified by the incorporation of dicumyl peroxide and maleic anhydride. The functionalized EPDM and modified PP were blended and cured dynamically at $190^{\circ}C$. The blend materials prepared in this study showed the comparable results to those of conventional TPE in terms of tensile and flow properties. Also, the odor component of recycled EPDM was analyzed using GC-MS.

• 고무기술
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• 제1권1호
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• pp.87-94
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• 2000

• 한국운동역학회지
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• 제25권1호
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• pp.103-111
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• 2015

Objective : The purpose of this study was to evaluate the effect for running shoes with resilience of midsole on biomechanical properties. Methods : 10 healthy males who had no history of injury in the lower extremity with an average age of 26.5 year(SD=1.84), height of 172.22 cm(SD=4.44) and weight of 67.51 kg(SD=6.17) participated in this study. All subjects ran on the treadmill wearing three different running shoes. Foot pressure data was collected using Pedar-X system(Novel Gmbh, Germany) operating at 100 Hz. Surface EMG signals for biceps femoris, rectus femoris, vastus lateralis, medial lateralis, tibialis anterior, medial gastrocnemius, soleus and peroneus longus were acquired at 1000 Hz using Bignoli 8 System(Delsys Inc., USA). To normalize the difference of the magnitude of muscle contractions, it was expressed as a percentage relative to the maximum voluntary contraction (MVC). The impact resilience of the midsole data was collected using Fastcam SA5 system(Photron Inc., USA). Collected data was analyzed using One-way ANOVA in order to investigate the effects of each running shoes. Results : TPU midsole was significantly wider in contact area than EVA, TPE midsole in midfoot and higher in EMG activity than EVA midsole at biceps femoris. TPE midsole was significantly wider in contact area than EVA midsole in rearfoot and higher in peak pressure than EVA midsole in forefoot. EVA midsole was significantly higher in EMG activity than TPU midsole at tibia anterior. In medial resilience of midsoles, TPE midsole was significantly higher than EVA, TPU midsole. Conclusion : TPU midsole can reduce the load on the midfoot effectively and activate tibialis anterior, biceps femoris to give help to running.

• 폴리머
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• 제37권5호
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• pp.571-578
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• 2013

다양한 조성의 ethylene propylene diene rubber(EPDM)/polyamide12(PA12) 용융 혼합물에 전자선 조사를 함으로써 열가소성 탄성체(thermoplastic elastomer, TPE)의 특성을 보이는 소재를 제조하였다. EPDM과 PA12 상 사이의 상용화제로 말레산화 EPDM(mEPDM)을 첨가함으로써 EPDM/PA12 용융 혼합물의 기계적 물성을 향상시켰다. 또한 EPDM/PA12 용융 혼합물에 0~100 kGy의 전자선을 조사함으로써 EPDM 사슬간의 선택적인 가교 반응을 유도함과 동시에 PA12 상으로부터 용융 유동성을 확보할 수 있었다. 결과적으로 EPDM/PA12 용융 혼합물에 mEPDM을 첨가한 후 전자선을 25 kGy 조사함에 의하여 열가소성 용융 거동을 보이면서도 물성 및 탄성체 성질이 우수한 EPDM/PA12 용융 혼합물을 제조할 수 있었다.

• Elastomers and Composites
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• 제48권1호
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• pp.24-29
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• 2013

식물성 오일로부터 추출한 물질을 기반으로 하여 열가소성 탄성체(thermoplastic elastomer, TPE) 중에서도 뛰어난 물성을 가진 것으로 잘 알려진 폴리아미드계 TPE(polyamide-type TPE, TPAE)의 단량체 합성공정을 개발하였다. 대다수의 식물성 오일에 함유되어 있는 불포화 지방산으로 잘 알려진 올레인산을 사용하여 TPAE의 단량체 6종($C_9$, $C_{10}$, $C_{11}$ ${\omega}$-amino acid 와 ${\alpha}$, ${\omega}$-dicarboxylic acid)을 좋은 수율로 합성하였다.

• Tuberculosis and Respiratory Diseases
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• 제42권4호
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• pp.455-464
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• 1995

연구배경: 인체의 결핵균 감염에 대하여 체액성 면역과 세포 매개성 면역이 함께 관여하며 효소결합 면역 분석법으로 결핵균 항원에 대한 항체(IgG)를 측정하는 것은 결핵성 흉막염 진단법으로 이용할 수 있다. 방법: 1992년 5월부터 1994년 7월까지 인하대학교 인하병원에 흉막염으로 입원하였던 환자 중 원인이 확진된 결핵성 흉막염 환자 40예, 비결핵성 흉막염 환자 19예를 대상으로 하여 혈청 및 흉막액에서 PPD 항원과 LAM-B 항원에 대한 IgG 항체가의 흡광도를 측정 하였다. 결과: 1) 결핵성 흉막염군의 흉막액 및 혈청내 PPD와 LAM-B 항체가는 비결핵성 흉악염군보다 유의하게 높았다.(p<0.0005) 2) 혈청내 PPD와 LAM-B 항체가는 흉막액내 항체가 보다 높았다. 3) PPD와 LAM-B에 대한 흉막액 항체와 혈청 항체간에는 의미있는 상관관계를 보였다. 4) 흉막액 PPD 항체의 결핵성 흉막염 진단기준을 0.091로 할 경우 진단적 예민도는 55.0%, 94.7%를 나타내었다. 5) 흉막액 LAM-B 항체의 결핵성 흉막염 진단기준을 0.337로 할 경우 진단적 예민도는 50.0%, 특이도는 94.7%를 나타내었다. 5)결핵성 흉막염군의 진단 양성률은 PPD 피부반응 검사, 흉막액의 양, 활동성 폐결핵 동반여부 등에 의해 영향받지 않았다. 결론: PPD와 LAM-B에 대한 IgG 측정은 결핵성 흉막염의 진단에 도움을 줄 것으로 사료된다. 아울러 PPD와 LAM-B에 대한 IgG는 수동적으로 흉막조직을 통해 혈청에서 흉막액으로 이동함을 제시하고 있다.

• Tuberculosis and Respiratory Diseases
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• 제80권1호
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• pp.77-82
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• 2017

Background: Delayed hypersensitivity plays a large role in the pathogenesis of tuberculous pleural effusion (TPE). Macrophages infected with live Mycobacterium tuberculosis (MTB) increase the levels of adenosine deaminase2 (ADA2) in the pleural fluid of TPE patients. However, it is as yet unclear whether ADA2 can be produced by macrophages when challenged with MTB antigens alone. This study therefore evaluated the levels of ADA2 mRNA expression, using monocyte-derived macrophages (MDMs) stimulated with MTB antigens. Methods: Purified monocytes from the peripheral blood mononuclear cells of healthy volunteers were differentiated into macrophages using granulocyte-macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF). The MDMs were stimulated with early secretory antigenic target protein 6 (ESAT6) and culture filtrate protein 10 (CFP10). The mRNA expression levels for the cat eye syndrome chromosome region, candidate 1 (CECR1) gene encoding ADA2 were then measured. Results: CECR1 mRNA expression levels were significantly higher in MDMs stimulated with ESAT6 and CFP10, than in the unstimulated MDMs. When stimulated with ESAT6, M-CSF-treated MDMs showed more pronounced CECR1 mRNA expression than GM-CSF-treated MDMs. Interferon-${\gamma}$ decreased the ESAT6- and CFP10-induced CECR1 mRNA expression in MDMs. CECR1 mRNA expression levels were positively correlated with mRNA expression of tumor necrosis factor ${\alpha}$ and interleukin 10, respectively. Conclusion: ADA2 mRNA expression increased when MDMs were stimulated with MTB antigens alone. This partly indicates that pleural fluid ADA levels could increase in patients with culture-negative TPE. Our results may be helpful in improving the understanding of TPE pathogenesis.