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排序方式: 共有542条查询结果,搜索用时 609 毫秒
491.
492.
Low bandgap alternating polyfluorene copolymers in plastic photodiodes and solar cells 总被引:1,自引:0,他引:1
O.?Ingan?sEmail author M.?Svensson F.?Zhang A.?Gadisa N.K.?Persson X.?Wang M.R.?Andersson 《Applied Physics A: Materials Science & Processing》2004,79(1):31-35
We report a comparative study of plastic photodiodes using four different copolymers of fluorene, with a variation of alkyl side chain length and chemical structure. Photodiode materials are formed by blending the polymers with a fullerene derivative and spincoating the blend solution. A photovoltage of 1 V is obtained in devices, where the anode is a doped polymer and the cathode is LiF/Al. Monochromatic quantum efficiencies are better than 40% over most of the absorption range, and under solar light AM 1.5 simulation, we reach energy efficiencies beyond 2%. The high fill factors obtained in some of the devices indicate that these are of interest for more elaborate optimisation. Reasons for the benign electrical transport are discussed. PACS 73.50.Pz; 73.61.Ph 相似文献
493.
494.
Ohrwall G Tchaplyguine M Lundwall M Feifel R Bergersen H Rander T Lindblad A Schulz J Peredkov S Barth S Marburger S Hergenhahn U Svensson S Björneholm O 《Physical review letters》2004,93(17):173401
A quantitative determination of 2s vacancy lifetimes in surface and bulk atoms of free Ne clusters has been made. While for free atoms the 2s inner-valence hole has a ps lifetime, it reduces to 6+/-1 fs for cluster bulk atoms. For surface atoms, the lifetime is on average longer than 30 fs. The lifetime estimate was obtained from fits of high-resolution photoelectron spectra of Ne clusters. The shortening of the lifetime is attributed to the coordination dependent interatomic Coulombic decay, which is extremely sensitive to internuclear distances. 相似文献
495.
Here we demonstrate, for the first time experimentally, a nanopipette action for metals using multiwalled carbon nanotubes. The process relies on electromigration forces, created at high electron current densities, enabling the transport of material inside the hollow core of carbon nanotubes. In this way nanoparticles of iron were transported to and from electrically conducting substrates. 相似文献
496.
We show that for every potential space , there exists an approach region for which the associated maximal function is of weak-type, but the boundedness for the completed region is false, which is in contrast with the nontangential case.
497.
Svante Janson 《Arkiv f?r Matematik》1993,31(2):307-338
We extend recent results by Pisier onK-subcouples, i.e. subcouples of an interpolation couple that preserve theK-functional (up to constants) and corresponding notions for quotient couples. Examples include interpolation (in the pointwise
sense) and a reinterpretation of the Adamyan-Arov-Krein theorem for Hankel operators.
This work was done at the Mittag-Leffler Institute. I am particularly grateful to Richard Rochberg for helpful discussions. 相似文献
498.
499.
U. Gelius E. Basilier S. Svensson T. Bergmark K. Siegbahn 《Journal of Electron Spectroscopy and Related Phenomena》1973,2(4):405-434
A new ESCA instrument with a fine-focussing X-ray monochromator, a high power electron gun, a rotating anode and a computerized multi-detector system is described. The instrument is suitable for the study of both solids and gases. The improved performance of the instrument is illustrated by a number of new spectra. Thus, spectra of gold, neon, methane, air, trifluoroacetate, thiophene and carbonyl sulphide, carbon monoxide, nitrogen, benzene and trithiapentalene are reported. 相似文献
500.