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33.
Urbina A Echeverría I Pérez-Garrido A Díaz-Sánchez A Abellán J 《Physical review letters》2003,90(10):106603
We have prepared solutions of multiwalled carbon nanotubes in Aroclor 1254, a mixture of polychlorinated biphenyls. The solutions are stable at room temperature. Transport measurements were performed using a scanning-tunneling probe on a sample prepared by spin coating the solution on gold substrates. Conductance steps were clearly seen. A histogram of a high number of traces shows maximum peaks at integer values of the conductance quantum G(0)=2e(2)/h, demonstrating ballistic transport at room temperature along the carbon nanotube over distances longer than 1.4 microm. 相似文献
34.
Moores A Mézailles N Ricard L Mathey F Le Floch P 《Chemical communications (Cambridge, England)》2003,(15):1914-1915
Reaction of a tetraphenyl-1,2-diphosphinyl dianion with [FeCl2(THF)1.5] or [Ru(COD)(acac)2] yields dianionic complexes which further react with Ph3SnCl to afford the corresponding bis(1,4-diphosphabutadiene) complexes. 相似文献
35.
Rosa P Mézailles N Ricard L Mathey F Le Floch P 《Angewandte Chemie (International ed. in English)》2001,40(23):4476-4479
36.
Rosa P Mézailles N Ricard L Mathey F Le Floch P Jean Y 《Angewandte Chemie (International ed. in English)》2001,40(7):1251-1253
37.
Borisenko SV Golden MS Legner S Pichler T Durr C Knupfer M Fink J Yang G Abell S Berger H 《Physical review letters》2000,84(19):4453-4456
On the basis of angle-scanned photoemission data recorded using unpolarized radiation, with high (E,k) resolution, and an extremely dense sampling of k space, we resolve the current controversy regarding the normal state Fermi surface (FS) in Bi(2)Sr(2)CaCu(2)O(8+delta). The true picture is simple, self-consistent, and robust: the FS is holelike, with the form of rounded tubes centered on the corners of the Brillouin zone. Two further types of features are also clearly observed: shadow FSs, which are most likely to be due to short range antiferromagnetic spin correlations, and diffraction replicas of the main FS caused by passage of the photoelectrons through the modulated Bi-O planes. 相似文献
38.
M. Ludwig P. Abell 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(1):97-105
Social networks in communities, markets, and societies self-organise through the interactions of many individuals. In this
paper we use a well-known
mechanism of social interactions — the balance of sentiment in triadic
relations — to describe the development of social networks. Our model
contrasts with many existing network models, in that people not only
establish but also break up relations whilst the network evolves. The
procedure generates several interesting network features such as a variety
of degree distributions and degree correlations. The resulting network
converges under certain conditions to a steady critical state where temporal
disruptions in triangles follow a power-law distribution. 相似文献
39.
Ricard Martí 《Journal of Combinatorial Theory, Series A》2008,115(4):547-568
Let k=Fq be a finite field. We enumerate k-rational n-sets of (unordered) points in a projective space PN over k, and we compute the generating function for the numbers of PGLN+1(k)-orbits of these n-sets. For N=1,2 we obtain a formula for these numbers of orbits as a polynomial in q with integer coefficients. 相似文献