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971.
Coiled strip can be directly produced through the twin-roll strip casting process from the melt by incorporating casting and hot rolling together into a single step. In this unique process, the strip formation from the molten metal critically relies upon the casting rolls. Thus, the design of the rolls is extremely essential. The coupled heat transfer and deformation analysis of the casting roll is carried out in a two-dimensional numerical model, using a finite element program (MARC) to examine the thermal stress and displacement. The effects of several factors such as the nickel overlay thickness on the roll surface, the casting speed, and the roll diameter on thermal characteristics are investigated. 相似文献
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973.
KNa[CoIII(OH)7{Mo6O17}] ·8H2O is obtained by ion‐exchange from a solution of K3 [Co(μ3‐OH)6Mo6O18] ·7H2O at ≈pH 1.4 using Amberlite IR120 ion exchange resin followed by concentrating the solution in a hot water bath. 相似文献
974.
Jong Eel Park Kyeong Wan Woo Sang Un Choi Je Hyun Lee Kang Ro Lee 《Helvetica chimica acta》2014,97(1):56-63
Two new spirostane‐steroidal saponins, bletilnoside A ( 1 ) and bletilnoside B ( 2 ), together with five known compounds, 3 – 7 , were isolated from the roots of Bletilla striata (Thunb .) Reichb . F. The structures of the new compounds were determined based on their 1D‐ and 2D‐NMR spectral data. The isolated compounds 1 – 7 were tested for cytotoxicity against four human tumor cells (A549, SK‐OV‐3, SK‐MEL‐2, and HCT15) in vitro using a sulforhodamin B bioassay, and compounds 1, 2 , and 5 showed significant cytotoxicities against all tested tumor cell lines with IC50 values ranging from 3.98±0.16 to 12.10±0.40 μM . 相似文献
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976.
Kyoungmi Hwang Kyungsik Lee Chungmok Lee Sungsoo Park 《The Journal of the Operational Research Society》2015,66(3):434-449
We propose two multi-class classification methods using a signomial function. Each of these methods directly constructs a multi-class classifier by solving a single optimization problem. Since the number of possible signomial terms is extremely large, we propose a column generation method that iteratively generates good signomial terms. Both of these methods obtain better or comparable classification accuracies than existing methods and also provide more sparse classifiers. 相似文献
977.
Yong Kyun Sim Suhyun Jung Jung Yun LimJuhyun Kim Seong-Ho KimBong Keun Song Bum Tae KimHyuk Lee Seongsoon Park 《Tetrahedron letters》2011,52(9):1041-1043
A facile process was developed to manufacture biocatalyst-conjugated magnetic nanobeads, which afford no loss of the intrinsic activity and enantioselectivity of biocatalysts. Up to 90% of their activities remained after six-time recycling in aqueous media. 相似文献
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