The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) i...The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) image simulations. From the Rietveld analysis it was shown that the nanowires had a monoclinic structure of the space group C2/M and the lattice parameters were a=1.5582 nm, 6=0.382 nm, c=0.9112 nm. HRTEM conclusions agree with refinement results obtained from experimental XRD data. The good agreement between the experimental and simulated images confirms that the nanowires is indeed K_2Ti_6O_13 nanowire.The growth axes of nanowires were mainly along the [010] direction.展开更多
The linear arboricity la(G) of a graph G is the minimum number of linear forests which partition the edges of G. Akiyama, Exoo and Harary conjectured that la(G) = [△(G)+1/2] for any regular graph G. In this paper, we...The linear arboricity la(G) of a graph G is the minimum number of linear forests which partition the edges of G. Akiyama, Exoo and Harary conjectured that la(G) = [△(G)+1/2] for any regular graph G. In this paper, we prove the conjecture for some composition graphs, in particular, for complete multipartite graphs.展开更多
基金This work was supported by the N ational Excellent Youth Foundation of China(Grant No.50025103)the National Natural Science Foundation of China(Grant No.20271037 and No.50171046)+1 种基金Major Project of National Natural Science Foundation of China(Grant No.90306014)Joint Project of NSFC and JSPS(No.50311140138).
文摘The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) image simulations. From the Rietveld analysis it was shown that the nanowires had a monoclinic structure of the space group C2/M and the lattice parameters were a=1.5582 nm, 6=0.382 nm, c=0.9112 nm. HRTEM conclusions agree with refinement results obtained from experimental XRD data. The good agreement between the experimental and simulated images confirms that the nanowires is indeed K_2Ti_6O_13 nanowire.The growth axes of nanowires were mainly along the [010] direction.
基金This work is partially supported by National Natural Science foundation of China Doctoral foundation of the Education Committee of China.
文摘The linear arboricity la(G) of a graph G is the minimum number of linear forests which partition the edges of G. Akiyama, Exoo and Harary conjectured that la(G) = [△(G)+1/2] for any regular graph G. In this paper, we prove the conjecture for some composition graphs, in particular, for complete multipartite graphs.
