• Applied Chemistry for Engineering
• /
• v.21 no.4
• /
• pp.377-384
• /
• 2010

We perform a comparative study to investigate the properties of the new energetic chain extender (AzPD). A series of poly(glycidyl azide)/poly(tetramethylene oxide)-based energetic segmented polyurethane (GAP/PTMG ESPU) with different chain extender, which is 3-azidopropane-1,2-diol (AzPD), 1,4-butane diol (1,4-BD), or 1,5 pentane diol (1,5-PD), was synthesized by solution polymerization in dimethyl formamide (DMF) and their phase behaviors were investigated. The ESPUs were characterized with Fourier transform infrared-attenuated total reflection spectroscopy (ATR FT-IR), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The results of the ATR FT-IR analysis of the urethane carbonyl group region showed that the 'free' C=O fraction was higher in GAP/PTMG AzESPU (0.5) than GAP/PTMG BDESPU (0.44) and GAP/PTMG PDESPU (0.41) for 7 days samples after preparation and that it was similar in the range of 0.26~0.29 for three 60 days ESPU samples. DMA curves of the GAP/PTMG AzESPU for 7 days samples showed amorphous polymers, but GAP/PTMG BDESPU and GAP/PTMG PDESPU showed viscoelastic behaviors with rubbery plateau and the flow region. However, DMA curves of the GAP/PTMG AzESPU for 60 days samples showed viscoelastic behaviors with rubbery plateau and the flow region like GAP/PTMG PDESPU, but GAP/PTMG BDESPU did not show the flow region. From phase behaviors with ATR FT-IR, DSC and DMA analysis, GAP/PTMG AzESPU showed good phase-mixing between components. However, it represented viscoelastic behavior of TPE similar to GAP/PTMG PDESPM according to phase equilibrium progress with aging time.

• Journal of Nutrition and Health
• /
• v.48 no.5
• /
• pp.441-450
• /
• 2015

Purpose: The purpose of this study was to investigate the effects of hypertension relevant nutrition knowledge on practices for prevention of hypertension in Chinese college students studying in South Korea. Methods: We conducted a survey of 276 Chinese students studying more than three months in Korean universities who were aged 19 and older about hypertension and sodium relevant nutrition knowledge, intake of salty processed food, hypertension prevention practices, and stages of behavior change for hypertension. Results: The average score on the questionnaire for hypertension relevant nutritional knowledge was 40.62 out of 50 points, and the average score for sodium relevant nutritional knowledge was 24 out of 30 points. Kimchi was the most frequently eaten salty processed food. The average score for hypertension prevention practices was 3.10 out of 5 points. The behavior change stages for prevention of hypertension were contemplation (47.1%), action (32.2%), and pre-contemplation (20.7%). The students received high scores on nutrition knowledge and showed significantly higher scores on the action stage than on pre-contemplation or contemplation. Nutritional knowledge of hypertension and sodium showed positive correlation with hypertension prevention practices, whereas negative correlation with salty processed food intake. Conclusion: Development of an education program for Chinese students in Korea on hypertension and sodium relevant nutritional knowledge is needed so that they can practice for prevention of hypertension.

• Journal of Life Science
• /
• v.21 no.6
• /
• pp.858-864
• /
• 2011

The phenolic compounds of walnut extracts by various solvents were shown to be 24.3 mg/g in hot water, 34.4 mg/g in ethanol, 32.5 mg/g in methanol and 15.1 mg/g in acetone. In a comparison of phenolic compounds from hot water and different concentrations of ethanol, which are harmless, 60% ethanol extract and hot water extract were 34.7 mg/g, 24.6 mg/g. The electron donating ability (EDA) of walnut extracts in hot water and 60% ethanol were 78.1% and 80.6%. According to ABTS radical cation decolorization for antioxidant activity, hot water and 60% ethanol extract showed high antioxidant activities of 98.1% and 98.3%. Antioxidant protection factor (PF) were $1.1{\pm}0.2$ PF and $1.1{\pm}0.4$ PF in hot water and 60% ethanol extract. In TBARs inhibitory activity, each extract showed high antioxidant activities at 60% and 75%. Anti-inflammation effects of walnut extract were tested, and inhibition of NO was 50% in 100 ${\mu}g/ml$ phenolics. Inhibitory activity against iNOS and COX-2 were shown, through Western blot, to be 10% in 100 ${\mu}g/ml$ phenolics. Tyrosine inhibitory activity of 60% ethanol extract was 43%, and astringent effect of 60% ethanol extract was 55%. These results suggest that walnut extracts are suitable for functional cosmetics requiring skin-whitening and anti-wrinkle activity.