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Bae Kang-Yul
- Journal of Welding and Joining
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- v.23 no.4
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- pp.73-80
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- 2005
Arc blow being occurred by Electro-Magnetic force(EMF) during the electric arc welding prevents the formation of a sound weldment. In this study, the effects of arc position, groove size, tack weld and base plate on the EMF in a butt-joint welding of mild steel plate are analyzed by a computer simulation based on the finite element method. The EMF can be numerically identified to be caused by a difference of the magnetic flux-density between ahead of and behind the arc in case that the workpiece locates asymmetrically around the uc. When there exists an air gap of groove ahead of the arc in the welding direction, the similar magnetic force has been producted regardless of the arc position and the gap size. The tack weld alleviates the magnetic force to about one fourth at the finish end of the workpiece. The magnetic force can be also significantly reduced with the base plate to about one fifth at the start end of the workpiece containing a tack weld.
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김운진;노광석;조은자
- Journal of the East Asian Society of Dietary Life
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- v.12 no.6
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- pp.574-579
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- 2002
The effect of Woomegi Dduct mixed with Tack-ioo and So-ju, and made of glutinous rice flour added with various proportions of nonwaxy rice and wheat flour, were studied by the textural and the sensory characteristics. Springiness, gumminess of Woomegi Dduck added with wheat flour tended to be higher than the one with nonwaxy rice flour and cohesiveness tended to increase as the addition amount of glutinous rice flour increased. The degree of gelatinization tended to decrease as the addition of nonwaxy rice flour and wheat flour contents increased from 10 to 50% Overall sensory score of the sample with 50% of wheat flour added to the glutinous rice flour and mixed with Tack-joo was the highest.
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Chang, Sang-Moon;Choi, Jyung
- Applied Biological Chemistry
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- v.30 no.1
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- pp.1-8
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- 1987
The distribution of the surface charges in two kinds of peats and their physico-chemical properties have a been studied by means of the potentiometric titration and by ion adsorption in different strength of electrolytes. The organic matter contents were 43.3% and 53.7% in Yeong Yang peat and Peong Tack peat, respectively. Their X-ray diffractograms showed that quartz was dominant in both peats, and illite, kaolinite, hydrated-halloysite and feldspars were contained in a trace. Total acidic group contents was 1.257me/g in Poeng Tack peat that was a little more than of Peong Yang heat were pKa values of Yeong Yang and Poeng Tack peat were 13.1 and 12.65, respectively. The titration curves at different ionic strength of electrolytes crossed at pH 3.9 and 4.4 in Yeong Yang peat, and pH 3.8 and 4.0 in Peong Tack peat. The pH ranges of suspensions when the net surfacecharge of the peats varied from positive to negative value were $pH\;4.55{\sim}5.20\;(NaCl)$ and $pH\;3.95{\sim}5.70\;(CaCl_2)$ in Yeong Fang peat, and $pH\;4.15{\sim}5.40\;(NaCl)$ and $pH\;3.80{\sim}4.15\;(CaCl_2)$ in Peong Tack peat. Therefore it is apparent that the zero point of charge of these peats was about pH 4.0.
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Park, Young-Jun;Lim, Dong-Hyuk;Kim, Hyun-Joong;Song, Hyun-Suk;Kwon, Hyuk-Jin
- Journal of Adhesion and Interface
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- v.8 no.2
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- pp.15-21
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- 2007
To prepare a natural rubber-based pressure-sensitive adhesive (PSA) for protection film of opto- functionalized sheet, natural rubber (NR) was blended with a DCPD type tackifier and three types of aliphatic hydrocarbon resins, respectively. Also, to supply low cohesion strength of NR, in the fixed ratio of tackifier, synthetic rubber, styrene-isoprene-styrene (SIS) block copolymer was blended with NR as a function of SIS contents. PSA performance of prepared PSAs was evaluated using probe tack and peel strength. Probe tack of NR/tackifier blends was increased with increasing tackifier contents, and showed maximum peak. In addition, probe tack of NR/tackifier blends slightly increased with increasing softening point of aliphatic hydrocarbon resins. Their peel strength increased up to 50 wt% of tackifier contents, but in the over contents of tackifier, they showed stick-slip failure mode. Finally, probe tack of NR/SIS/tackifier blends showed the maximum values at 20~40 wt% of tackifier contents, but at 20 wt% of tackifier contents, they showed fibrillation. For this reason, peel strength showed maximum values at 40 wt% of tackifier contents.
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