• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.9
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• pp.1209-1215
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• 2010

The effects of multi-walled carbon nanotube (MWCNT) content, carbon black (CB) content, atmospheric-pressure flame plasma (APFP) treatment, and acid treatment on the mechanical properties of elastomeric composites were investigated. For pure or filled rubbers with the given amount of CB (20 and 40 phr), the tensile strength and modulus of the elastomeric composites increase similarly with the MWCNT content. A composite with APFP-treated MWCNTs shows a hardening effect (high strength, high modulus, and high ductility) unlike the one with untreated MWCNTs. On the other hand, a composite with APFP-treated CB shows a softening effect (high strength, low modulus, and high ductility), which is unlike a composite with untreated CB. As the refluxing time increases from 1 h to 2 h and the sulfuric acid concentration increases from 60% to 90%, the tensile strength and modulus of a composite decrease. Thus, it is found that the MWCNT content, CB content, APFP treatment, sulfuric acid concentration, and refluxing time have an important effect on the mechanical properties of NBR composites.

• The Journal of Korean Obstetrics and Gynecology
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• v.30 no.4
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• pp.114-134
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• 2017

Objectives: This study aims to investigate the changes of women's postpartum symptoms, including their weights, edema index and quality of life (QOL) over the first six weeks after childbirth. Methods: The study participants were 31 postpartum women treated in the Dept. of Obstetrics & Gynecology, at Woo-Suk University Korean Medicine Hospital, from May 20th to August 5th, 2016. In the first 2 weeks of the postpartum period, the main data collection method was to interview each patient and write down all of their complaints, and additionally referring to each participant's PHR (Personal Health Records). At the 3rd, 4th, 5th and 6th week, the researcher interviewed participants by phone once a week. The participants' weight, edema index (ECW/TBW) and the quality of life (by EQ-VAS) were measured at 1st and 2nd week after childbirth. And, EQ-VAS was assessed once more at the 6th week after childbirth. As a last step, the participants responded to a survey on satisfaction regarding their postpartum care with Korean Medicine. Results: 1. In the 1st one week after childbirth, edema was the most frequent complaint. It was about joint pain of the upper limbs in the 2nd and 3rd weeks, sweating in the 4th week, and joint pain of the upper limbs in the 5th and the 6th weeks. 2. In the 1st two weeks of the postpartum period, the weight of the participants decreased from $66.33{\pm}9.30kg$ to $62.60{\pm}8.92kg$ (p<0.001) and the edema index ECW/TBW decreased from $0.399{\pm}0.010$ to $0.385{\pm}0.0 4$ (p<0.001). The EQ-VAS significantly improved from $61.77{\pm}17.72$ to $73.51{\pm}14.67$ (p<0.001). In the last 4-weeks of the postpartum period, the EQ-VAS decreased from $74.30{\pm}14.25$ to $73.63{\pm}13.35$, but this difference was not statistically significant (p=0.749). 3. Regarding the satisfaction with postpartum care with Korean Medicine, 60% of the participants responded that it was 'Excellent' and 40% said it was 'Good'. Conclusion: Over the entire postpartum period, the most frequent complaints were about musculoskeletal symptoms. Postpartum care with Korean Medicine treatments in the early postpartum period improves various postpartum symptoms and the quality of life for postpartum women.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.104-108
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• 2011

In the non-conductive adhesives (NCAs) for adhesion of micro electro mechanical system (MEMS), there are some problems such as delamination and cracking resulting from the large differences of coefficients of thermal expansion (CTE) between NCAs and substrates. So, the addition of inorganic particles such as silica and nano clay to the CTEs composit have been applied to reduce the CTEs of the adhesives. Additions of the flexibilizers such as siloxanes have also been performed to improve the flexibility of epoxy composite. Amino modified siloxane (AMSs) were used to improve compatibility between epoxy and siloxane. In this study, glass transition temperatures (Tg) and moduli of those composites were measured to confirm the effects of AMS with two different equivalents on thermal/mechanical properties of AMS/epoxy composites. Tg of KF-8010/epoxy composites decreased from 148 to $122^{\circ}C$ and those of X-22-161A/epoxy composites decreased from 148 to $121^{\circ}C$. Moduli of KF-8010/epoxy composites decreased from 2648 to 2143 MPa by adding KF-8010 and moduli of X-22-161A/epoxy composites decreased from 2648 to 2014 MPa. In short, using long Si-O chain AMS leads to a greater decrease in moduli. However, haven't showed significant differences in Tg's.