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71.
J. Ederth A. Hultåker G.A. Niklasson P. Heszler A.R. van Doorn M.J. Jongerius D. Burgard C.G. Granqvist 《Applied Physics A: Materials Science & Processing》2005,81(7):1363-1368
Electrical and optical properties were investigated in porous thin films consisting of In2O3:Sn (indium tin oxide; ITO) nanoparticles. The temperature-dependent resistivity was successfully described by a fluctuation-induced tunneling model, indicating a sample morphology dominated by clusters of ITO nanoparticles separated by insulating barriers. An effective-medium model, including the effect of ionized impurity scattering, was successfully fitted to measured reflectance and transmittance. Post-deposition treatments were carried out at 773 K for 2 h in both air and vacuum. It is shown that vacuum annealing increases either the barrier width or the area between two conducting clusters in the samples and, furthermore, an extra optical absorption occurs close to the band gap. A subsequent air annealing then reduces the effect of the barriers on the electrical properties and diminishes the absorption close to the band gap. PACS 72.80.Jc; 81.07.Bc; 81.40.Tv 相似文献
72.
This paper covers three aspects of electrochromic smart windows. Their energy efficiency is discussed, and it is argued that
a control strategy considering whether a room is in use or not can lead to large savings of the energy needed for space cooling.
With regard to durability, it is shown that chemical compatibility between the electrolyte and electrochromic films of tungsten
oxide and nickel oxide can be achieved without loss of optical transparency. Finally, we consider device manufacturability
and present data on precharging of electrochromic nickel oxide films by ozone treatment.
Electronic Publication 相似文献
73.
74.
Mean oscillation and commutators of singular integral operators 总被引:24,自引:0,他引:24
Svante Janson 《Arkiv f?r Matematik》1978,16(1):263-270
75.
76.
Let S be a finite set of graphs and t a real number, 0 < t < 1. A (deterministic) graph G is (t, 5)-proportional if for every H ∈ S, the number of induced subgraphs of G isomorphic to H equals the expected number of induced copies of H in the random graph Gn, t where n = |V(G)|. Let Sk = {all graphs on k vertices}, in particular S3 = {K3, P2, K2Kt, D3}. The notion of proportional graphs stems from the study of random graphs (Barbour, Karoński, and Ruciński, J Combinat. Th. Ser. B, 47 , 125-145, 1989; Janson and Nowicki, Prob. Th. Rel. Fields, to appear, Janson, Random Struct. Alg., 1 , 15-37, 1990) where it is shown that (t, S3)-proportional graphs play a very special role; we thus call them simply t-proportional. However, only a few ½-proportional graphs on 8 vertices were known and it was an open problem whether there are any f-proportional graphs with t ≠ ½ at all. In this paper, we show that there are infinitely many ½-proportional graphs and that there are t-proportional graphs with t≠. Both results are proved constructively. [We are not able to provide the latter construction for all f∈ Q∩(0,1), but the set of ts for which our construction works is dense in (0,1).] To support a conviction that the existence of (t, S3)-proportional graphs was not quite obvious, we show that there are no (t, S4)-proportional graphs. 相似文献
77.
Svante Janson 《Random Structures and Algorithms》2003,22(4):337-358
Asymptotics are obtained for the mean, variance, and higher moments as well as for the distribution of the Wiener index of a random tree from a simply generated family (or, equivalently, a critical Galton–Watson tree). We also establish a joint asymptotic distribution of the Wiener index and the internal path length, as well as asymptotics for the covariance and other mixed moments. The limit laws are described using functionals of a Brownian excursion. The methods include both Aldous' theory of the continuum random tree and analysis of generating functions. © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 22: 337–358, 2003 相似文献
78.
Svante Janson 《Acta Appl Math》1994,34(1-2):5-6
The concentration function of a random variable may be estimated using couplings of the variable with itself.Supported by the Göran Gustafsson Foundation for Research in Natural Sciences and Medicine. 相似文献
79.
Parallel band absorption at 1.55 eV, which is clearly seen in bulk aluminium, becomes much less visible in transmittance spectra on films consisting of gas evaporated particles with diameters of 3 to 4 nm. This can be understood, at least partially, from an enhancement of the Drude absorption caused by the lowered electron lifetime. 相似文献
80.
Reidar Arneberg Hans Ågren Per-Åke Malmquist Svante Svensson 《Chemical physics letters》1982,92(2):125-130
A high-resolution core photoelectron spectrum of free acetylene is presented. Configuration interaction and complete active space SCF calculations were carried out for assignment and prediction of energies and intensities in the spectrum. The shake-up structure is found to be strongly dominated by intervalence πg to πg transitions for which multiple 2-, 3- and 4-fold excitations are important. 相似文献