• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.447-451
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• 2007

This study was carried out to examine the antioxidant activity of Gynostemma pentaphyllum Makino. Using the DPPH method, we found that free radical scavenging activity was strong in all the fractions except the water fraction of the water extract (GPW) and ethanol extract (GPE) of G pentaphyllum Makino. Pseudo-SOD activity was highest in the diethyl ether fraction of the ethanol extract, while the other fractions of the ethanol and water extracts were lower. For xanthine oxidase inlribition activity, the diethyl ether fraction and butanol fraction of GPW, and the diethyl ether fraction and butanol fraction of GPE, showed activities over 80%. Nitrite scavenging ability was strong (over 60%) in all the GPW and GPE fractions. The diethyl ether fraction and butanol fraction of GPW had more effective nitrite scavenging abilities than the other extract fractions. These results suggest that the extracts of G pentaphyllum Makino can be used as a functional material in a tea or drink.

• Advances in concrete construction
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• v.6 no.5
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• pp.509-525
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• 2018

In this paper the application of forging process as benefit technique in Reinforced Concrete (RC) beam bars and comparison to lap splices was experimentally investigated with four concrete beam specimens with same dimensions and reinforcement details. The reference specimen was with no splices and the other three beams were with different splices (100% forging in the middle, 50% forging, and 100% lap splices in the middle). Beams were tested with the four points load system. Experimental test results indicated that using forging process as new bar splicing method can have high effects on increasing ductility and energy dissipation of concrete structures. It also proved that this method increased the flexural rigidity, energy absorption, and ductility of the RC beams. And also this research results showed that the flexural capacity and ductility of the beam with 50% forging were respectively increased up to 10% and 75% comparing to that of reference specimen, but the energy absorption of this beams was decreased up to 27%. The ductility of beam with 50% forging was increased up to 25% comparing the ductility of beam with 100% forging.