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31.
N. Verma Petrus C. Pistorius Richard J. Fruehan Michael Potter Minna Lind Scott R. Story 《Metallurgical and Materials Transactions B》2011,42(4):720-729
The formation of intermediate reaction products after calcium addition to aluminum-killed steel was studied. Steel samples were taken from laboratory and industrial heats before and at various times after calcium treatment. Inclusions were characterized by automated and manual scanning electron microscopy and X-ray microanalysis of polished cross sections and inclusions extracted by dissolution of the steel. Industrial and laboratory melts containing more than 40 parts per million (by mass) of dissolved sulfur showed calcium sulfide as the main reaction product after calcium injection, with calcium aluminates appearing later. It is proposed that the calcium aluminates are formed by reaction between the calcium sulfide and the alumina. A laboratory heat containing 7 parts per million of sulfur showed calcium oxide as the main initial calcium reaction product. A simple mechanism is proposed for the modification of alumina inclusions by calcium, considering transient CaO and CaS formation. 相似文献
32.
Silicon - Silicon carbide piezoresistive pressure sensor is more suitable for harsh environment due to its wide bandgap, corrosion tolerance, excellent chemical inertness, high Young’s... 相似文献
33.
English-type fresh skinless pork sausages in which 30% of the protein was replaced by unheated chickpea flour or by chickpea flour heated at 80°C for 1 h were evaluated microbiologically. During storage at 0°C, but not 22°C, incorporation of unheated chickpea flour lowered the microbiological quality of the sausages, but incorporation of chickpea flour previously heated at 80°C for 1 h led to no less of microbiological quality. 相似文献
34.
Fluidization and heat transfer experiments have been conducted in gas fluidized beds of two different sizes, viz., 305 × 305 mm2 and 305 × 152.5 mm2 and with particles of silica sands (), glass beads (dp = 427 μm) and millet seeds (dp = 2064 μm) with immersed smooth vertical heated tubes of diameter 12.7, 28.6, and 50.8 mm. Important conclusions are drawn concerning the dependence of heat transfer coefficient on fluidization velocity, bed particle diameter, tube diameter and nature of bed fluidization. The heat transfer data are employed to assess the available literature correlations for heat transfer coefficient and for its maximum value. 相似文献
35.
Yang Chao-Tung Chen Shuo-Tsung Liu Jung-Chun Chan Yu-Wei Chen Chien-Chih Verma Vinod Kumar 《The Journal of supercomputing》2019,75(8):4408-4429
The Journal of Supercomputing - In the last decade, cloud computing has brought enormous changes to people’s lives. Cloud computing gives a client-driven computational model. In this case,... 相似文献
36.
Singh Bikesh K. Jain Pankaj Banchhor Sumit K. Verma Kesari 《Multimedia Tools and Applications》2019,78(16):22421-22444
Multimedia Tools and Applications - Performance of computerized diagnostic systems yearning to be approved by medical regulatory bodies must meet the expectations of human experts. Highly accurate... 相似文献
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Comprehensive review for energy efficient hierarchical routing protocols on wireless sensor networks
Wireless Networks - In recent years, wireless sensor networks (WSNs) have played a major role in applications such as tracking and monitoring in remote environments. Designing energy efficient... 相似文献
39.
Two residues that may ligate Ca2+ in transmembrane domain six of the plasma membrane Ca(2+)-ATPase 总被引:1,自引:0,他引:1
AO Adebayo A Enyedi AK Verma AG Filoteo JT Penniston 《Canadian Metallurgical Quarterly》1995,270(46):27812-27816
In order to identify Ca2+ ligands in the putative transmembrane domain 6 of the plasma membrane Ca2+ pump, amino acids Asn879, Met882, Asp883, and Ser887 were singly altered. Asn879, Met882, and Asp883 were chosen because the corresponding amino acids have been proposed as Ca2+ ligands in the sarcoplasmic reticulum Ca2+ pump (Clarke, D. M., Loo, T. W., and MacLennan, D. H. (1990) J. Biol. Chem. 265, 6262-6267). For the alterations, a fully active truncated version of the pump was used, because the interaction of Ca2+ with the pump could be studied without interference from calmodulin binding. The mutants at Asn and Asp did not carry out ATP-supported Ca2+ uptake and formed no acylphosphate from [gamma-32P]ATP, suggesting that, like the corresponding amino acids in the sarcoplasmic reticulum Ca2+ pump, these two are Ca2+ ligands. However, all the mutants at the position of Met882 showed some activity. Indeed, the Met882--> Ile mutant was fully active at a saturating Ca2+ concentration and only the K1/2 for Ca2+ activation was shifted slightly upward. Converting the Met to Thr (which is the corresponding residue in the sarcoplasmic reticulum Ca2+ pump) reduced the activity to 20% of the wild type, further emphasizing the differences between the two Ca2+ pumps. The mutant Ser887--> Ala was expressed in greater amounts than, and had a specific activity about 50% higher than, the wild type, indicating that this serine also could not be a Ca2+ ligand and could not replace the missing Thr at position Met882. 相似文献
40.