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1.
Konstantinos Spyrou Matteo Calvaresi Evmorfia K. Diamanti Theodoros Tsoufis Dimitrios Gournis Petra Rudolf Francesco Zerbetto 《Advanced functional materials》2015,25(2):263-269
Experimental and theoretical studies are performed in order to illuminate, for first time, the intercalation mechanism of polycyclic aromatic molecules into graphite oxide. Two representative molecules of this family, aniline and naphthalene amine are investigated. After intercalation, aniline molecules prefer to covalently connect to the graphene oxide matrix via chemical grafting, while napthalene amine molecules bind with the graphene oxide surface through π–π interactions. The presence of intercalated aromatic molecules between the graphene oxide layers is demonstrated by X‐ray diffraction, while the type of interaction between graphene oxide and polycyclic organic molecules is elucidated by X‐ray photoelectron spectroscopy. Combined quantum mechanical and molecular mechanical calculations describe the intercalation mechanism and the aniline grafting, rationalizing the experimental data. The present work opens new perspectives for the interaction of various aromatic molecules with graphite oxide and the so‐called “intercalation chemistry”. 相似文献
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I. Kasatkin F. Girgsdies T. Ressler R. A. Caruso J. H. Schattka J. Urban K. Weiss 《Journal of Materials Science》2004,39(6):2151-2157
The orientation relations m(100) || t(001), m[001] || t[110]; m(011) || t(100), m[100] || t[001]; m(100) || t(110), m[001] || t[001]; m(013) || t(116), m[001] || t[001] (indices for the primitive tetragonal cell) have been found between the tetragonal (t) and monoclinic (m) domains during the electron irradiation-induced m-t phase transition observed in-situ with HREM within isolated zirconia nanoparticles. Geometric models of the m-t interfaces are proposed. 相似文献
4.
Rudolf Habison 《International Journal of Project Management》1985,3(3):178-181
Meeting time and cost objectives in complex projects involves specific problems and risks. An attempt is made to analyse the components of total cost increase of a project caused by time delay. An outline is given as to how these considerations can be used to estimate cost increases in investors' decision situations as well as to ascertain fair contractual penalties and claims for compensation and for the evaluation of justified project acceleration costs. 相似文献
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S. O. Balanetskii B. Grushko K. Urban T. Ya. Velikanova 《Powder Metallurgy and Metal Ceramics》2004,43(9):480-483
Scanning and transmission electron microscopy have been combined with x-ray diffraction to examine the phase equilibria in the Al - Pd - Re system at 1000°C for compositions from 50 to 100 at.% Al, and the corresponding isothermal section has been constructed. The binary monoclinic Al3 Re phase has been observed for the first time. It is confirmed that there is a stable icosahedral phase in this system. The boundaries to its homogeneity region have been determined and the phase equilibria in which it participates. 相似文献
7.
J Weber P Majer J Litera J Urban M Soucek J Vondrásek J Konvalinka P Novek J Sedlácek P Strop HG Kr?usslich I Pichová 《Canadian Metallurgical Quarterly》1997,341(1):62-69
The results of investigation of haptoglobin (Hp) types in 596 donor blood samples in some towns of Ukraine (Dnepropetrovsk, Kharkov, Odessa, Kiev, Uzhgorod, Zhitomir) are presented. Three normal Hp types (Hp1-1, Hp2-1 and Hp2-2) have been found. The reliable interpopulation differences in the Hp types frequency were not found. On the whole the Hp types frequency in the type Hp1-1 comprised 12.7%. In the type Hp2-1-48.1% and in the type Hp2-2-36.5%. The frequency of the gene Hp1 is 0.38. The frequency of the Hp types and of the gene Hpl in Ukraine is similar to that in population of Eastern Europe and European Part of Russia. 相似文献
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The introduction of multiple, independent production lines has helped many firms to increase their production flexibility, provide for redundancy when equipment breaks down, reduce idle time and labor costs, and achieve many other benefits. This paper introduces and formalizes the multiple U-line balancing problem. Optimal solution methodologies are provided for Type I (minimize the number of stations for a given cycle time), Type II (minimize the cycle time for a given number of stations), and cost-minimization line-balancing problems. A branch-and-bound algorithm is also developed for the situation in which equipment requirements are dependent on the line configuration and the task assignment to stations. Computational results indicate that the greatest benefit of exploiting multiple lines occurs for smaller cycle-time problems that require higher output. 相似文献