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91.
First-principles method was performed to predict the effect of Ti addition on thickness and adhesion of 55 pct Al-Zn-1.6 pct Si coating. The results of optimized geometric configurations, total energy, and charge distributions for the Ti substitution in Fe2Al5 and FeAl3 phases indicated Ti will grab electronic charges from Al atoms, form bonds with neighboring Al, which will reduce the growth of Fe-Al intermetallic layers, and finally enhance the adhesion of the coating/substrate. Furthermore, experiments were performed to validate the prediction results of first-principles successfully.  相似文献   
92.
High performance β-polypropylene (β-PP) nanocomposites were prepared by nano-CaCO3 with β-nucleation (β-CC) filled PP, and the crystallization and mechanical properties of β-PP nanocomposites were investigated. The results show that β-CC prepared by nano-CaCO3 supported β-nucleating agent calcium pimelate (CaPA) does not only increase the crystallization temperature of PP, but also induce the forming of a number of β-PP. It indicates that the nucleation mechanism of nano-CaCO3 has been changed from α- to β-nucleation. The notched impact strength of β-CC filled PP nanocomposites was higher than that of CC filled PP and CaPA nucleated PP. It is suggested that there is a synergistic effect of toughening of CC and toughness of β-PP. Meanwhile, the reinforcing of CC nanoparticles increased the stiffness of β-PP. The synergistic toughening effect of CC and β-PP was discussed. This method can be extended to prepare other high performance filled β-PP composites.  相似文献   
93.
This paper develops cloud based software computing as a service (SCaaS) in the hybrid evolution algorithm with feedback assistance to solve the data optimal NP-complete problems such as travel salesman problems and job shop scheduling problems. Suitable steps, methods, or procedures of the genetic algorithm can be adopted from various evolution procedures or methods of the genetic algorithms based on the fitness evaluation results and survival ratio of different crossover methods in the current generation. The proposed system can dynamically emphasize the corresponding methods or procedures for the better performance in optimal solution searching. In addition, according to the proposed XML format, system users can upload only the coding of chromosomes without implementing the genetic algorithm program. Furthermore, by using the feedback assistance, the convergence time of the optimal solution can be enhanced.  相似文献   
94.
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. New insights into the pathogenesis of this lethal disease are urgently needed. Chromosomal copy number alterations (CNAs) can lead to activation of oncogenes and inactivation of tumor suppressors in human cancers. Thus, identification of cancer-specific CNAs will not only provide new insight into understanding the molecular basis of tumor genesis but also facilitate the identification of HCC biomarkers using CNA.  相似文献   
95.
European Journal of Wood and Wood Products - Medium density fibreboards (MDF) are currently not recycled after service life, but various publications report on recycling by the disintegration of...  相似文献   
96.
Neural Processing Letters - In this paper, problem of reachable sets bounding is considered for switched neural networks systems with mixed time-varying delays and bounded disturbances. By using...  相似文献   
97.
98.
This article describes findings of the correlation between the atomic scale surface structure and the electrocatalytic performance of nanoengineered Pt-Pd/C catalysts for oxygen reduction reaction (ORR), aiming at providing a new fundamental insight into the role of the detailed atomic decorated structure of the catalysts in fuel cell reactions. Carbon-supported Pt decorated Pd nanoparticles (donated as Pt-Pd/C), with Pt coverage close to a monolayer, were prepared from a simple galvanic replacement reaction between Pd/C particles and PtCl42? at room temperature. The decorated architecture was confirmed by extensive microstructural characterization techniques, including TEM, XRD, XPS, HAADF-STEM, ICP and HS-LEIS. The catalysts were also examined for their intrinsic kinetic activities towards oxygen reduction reaction. The results have shown that the Pt-Pd/C catalysts are highly active towards molecular oxygen electrocatalytic reduction. These findings have profound implications to the design and nanoengineering of decorated surfaces of catalysts for oxygen reduction reaction.  相似文献   
99.
本文提出采用阈值法、能量法、AIC法、Gabor法提取局部放电脉冲波前时刻,基于时间差(TOA)实现局部放电点自动定位算法.采用上述算法首先在实验室进行高压开关柜的局部放电点定位,并对比上述方法的优劣.然后,在变电站现场对一面存在疑似放电的开关柜进行定位,通过查看时域波形波前时刻特征以及自动定位两种方法检测,检测结果表明,放电点位于该开关柜上部间隔的母线处,停电检修的结果印证了现场检测结论,证明了本文提出算法的有效性.  相似文献   
100.
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