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991.
Ur?a?Opara?Kra?ovecEmail author Marko?Topi? Anneke?Georg Andreas?Georg Goran?Dra?i? 《Journal of Sol-Gel Science and Technology》2005,36(1):45-52
Nano-structured WO3-TiO2 layers were prepared by the sol-gel route. To obtain transparent, porous and crack free layers up to 0.8 μ m with a single dipping cycle a templating strategy was used. As a template three-dimensionally network based on organically modified silane was introduced to the WO3 and TiO2 sols. The WO3 layers were dip-coated onto the conductive glass substrate (TCO) and the TiO2 layers on the top of the WO3 layer. The morphology and the structure of the layers were determined by Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HR-TEM), Energy Dispersive X-Ray Spectroscopy (EDXS), Auger and Infrared spectroscopy. SEM image of the WO3-TiO2 layer confirmed the nano-porosity of the layers and give the size of the particles of about 10 nm for TiO2 and 30 nm for WO3 layer. Further analysis indicated that the titanium sol penetrates the WO3 layer. Particles in the WO3 layer consist of a crystalline monoclinic WO3 core surrounded by a 5–10 nm amorphous phase consisting of WO3, TiO2 and SiO2. The WO3-TiO2 layers were used to assemble all solid state photoelectrochromic (PE) devices. Under 1 sun irradiation (1000 W/m2) the visible transmittance of the PE device changes from 62% to 1.6%. The colouring and bleaching processes last about 10 minutes. 相似文献
992.
H.?J.?M.?BouwmeesterEmail author M.?W.?Den?Otter B.?A.?Boukamp 《Journal of Solid State Electrochemistry》2004,8(9):599-605
The surface exchange coefficient and chemical diffusion coefficient of oxygen for the perovskites La0.6Sr0.4Co1–yFeyO3– (y=0.2, 0.5 and 0.8) were measured using the conductivity relaxation technique. Measurements were performed between 600 and 800 °C in an oxygen partial pressure range between 10–4 and 1 bar. Both transport coefficients decrease markedly with decreasing oxygen partial pressure below about 10–2 bar at all temperatures. This is attributed to ordering of oxygen vacancies. Implications for using La0.6Sr0.4Co1–yFeyO3– as an oxygen separation membrane are discussed.Presented at the OSSEP Workshop Ionic and Mixed Conductors: Methods and Processes, Aveiro, Portugal, 10-12 April 2003 相似文献
993.
Fatty acid methyl esters from various fats and oils were separated by comprehensive two-dimensional supercritical fluid chromatography with conventional packed columns and FID detection. The first dimension was a silica gel column and the second dimension was an ODS column. This combination was largely orthogonal for the separation of fatty acid methyl esters. The first dimension separations were primarily based on the number of double bonds while the second dimension separations were based on the chain length. The highly-ordered chromatograms and improved resolution allowed the easy detection and identification of minor components. Although the first dimension separations were performed under isobaric conditions where the peak width increased in proportion to the retention, the programming of the sampling duration allowed us to maintain the optimum re-injection frequency (3–4 times) per peak into the second dimension and so to minimize the total analysis time without deteriorating the resolution. 相似文献
994.
Prof. Dr. Wolfgang Schwarz 《Monatshefte für Mathematik》1979,87(1):65-67
D. Leitmann andD. Wolke [3] proved that multiplicative functions, which are restrictions of continuous, periodic functionsF: with irrational period, are constant equal to 0 or 1. In this note a simpler proof for this result is given. 相似文献
995.
This paper is concerned with the optimal positioning of a new product in an attribute space. A deterministic optimization model that relies on the axiom of choice is compared with the model byShocker/Srinivasan [1974] that incorporates a probabilistic measure of choice. Investigating the assumptions and the construction of both models, it is shown that the probability function byShocker/Srinivasan is based on a controversial assumption and incorporates a parameter that has not been given an economic explanation. Furthermore, both models are applied to complex configurations. It is demonstrated that the optimal positions for the new product resulting from the model byShocker/Srinivasan depend heavily on the parameter just mentioned and may run contrary to plausible consequences of the axiom of choice.
Zusammenfassung Für die optimale Gestaltung neuer Produkte, d.h. ihrer Positionierung in einem Raum von Produkteigenschaften, wird ein Modell angeboten, das auf einer deterministischen Kaufentscheidung beruht, ein anderes, das eine stochastische Kaufentscheidung unterstellt. Es wird gezeigt, daß der zuletzt genannte Modelltyp stark von der Spezifikation eines ökonomisch bisher nicht erklärten Parameters abhängt und z.T. Konsequenzen aufweist, die dem Wahlaxiom zuwider laufen, auf das das erstgenannte Modell aufbaut. Durch einen Vergleich auch komplexer Konfigurationen von Käuferbeurteilungen neuer Produkte wird gezeigt, welche Gestaltungsentscheidungen auf der Grundlage der beiden Modelle zur Optimierung einer Zielfunktion zu treffen sind.相似文献
996.
LetG denote a locally compact abelian topological group. The aim of the present paper is to prove an “intermediate” result between two well-known results ofL. Hörmander andG. I. Gaudry concerning the structure of the spaces ?G?μ?t p,q (G). 相似文献
997.
Prof. Dr. A. Charnes Associate Prof. Dr. W. Raike Dr. J. Stutz 《Mathematical Methods of Operations Research》1975,19(3):115-121
Summary Strong theorems concerning globally unique solutions to nonlinear inequalities have been obtained byGale andNikaido via P-matrix characterizations of theJacobians of the mappings involved. We introduce two new concepts here: v-positivity and the poverse. These permit us to state and prove significant generalizations of the theorems just mentioned and, equally important, provide access to preliminary results concerning linear inequalities by the powerful direct techniques of linear programming theory.
This Research was partly supported by Project No. NR 047-021, ONR Contracts NO 0014-67-A-0126-0008 and NO 0014-67-A-0126-0009 with the Center for Cybernetic Studies, The University of Texas. 相似文献
Zusammenfassung Gale undNikaido haben starke Sätze über globale, eindeutige Lösungen nichtlinearer Ungleichungen erhalten für den Fall, daß dieJacobi- Matrix der auftretenden Abbildung eineP-Matrix ist. Darauf aufbauend werden zwei neue Konzepte vorgestellt: v-positivity und die poverse. Diese erlauben es, Verallgemeinerungen der erwähnten Sätze aufzustellen und zu beweisen und, was von gleicher Bedeutung ist, die Verbindung zu früheren Ergebnissen über lineare Ungleichungen durch die wirkungsvollen direkten Verfahren der Theorie der Linearen Optimierung herzustellen.
This Research was partly supported by Project No. NR 047-021, ONR Contracts NO 0014-67-A-0126-0008 and NO 0014-67-A-0126-0009 with the Center for Cybernetic Studies, The University of Texas. 相似文献
998.
Prof. Dr. Wolfgang M. Schmidt 《Monatshefte für Mathematik》1976,82(3):237-245
The first question is about a possible variation on Dirichlet's approximation theorem for linear forms x+y+z, wherex,y are restricted topositive integers. The second question, which turns out to be related to the first, is about approximation to elements in a power series fieldk((t
–1)) by solutions of first order linear differential equationsx+y+z=0, wherex,y,z are polynomials int.
Dedicated to Prof. Dr. E. Hlawka on the occasion of his 60th birthday 相似文献
999.
H. Spieler H. J. K?rner K. E. Rehm M. Richter H. P. Rother 《Zeitschrift für Physik A Hadrons and Nuclei》1976,53(5):241-250
The reactions120Sn+72 MeV18O and122Sn+74 MeV16O were investigated with time of-flightE-E-telescopes. Data are presented for all quasi-elastic reaction channels. The two neutron stripping and pickup reactions (18O,16O), (18O,20O) and (16O,18O) are analyzed in detail. It is shown that these heavy ion induced two neutron transfer reactions proceed with essentially the same type of selectivity as the corresponding light ion induced reactions. The differential cross sections for transfer reactions leaving the120, 122Sn nuclei in their 2+ first excited states are shown to be influenced by interference effects due to additional inelastic excitations. 相似文献
1000.
I. Tserruya R. Schulé H. Schmidt-B?cking K. Bethge 《Zeitschrift für Physik A Hadrons and Nuclei》1976,89(1):233-241
TheK-shell ionization cross sections of Mn, Ni, Cu, Zn and Ge under32S bombardment have been measured in the energy range from 5 to 48 MeV. The cross sections are compared with available theories based on a direct Coulomb ionization mechanism and with the predictions of theK-vacancy sharing process. This last process can reasonably account for the measured cross sections at high bombarding energies. The energy shifts of theK
- andK
-lines and theK
/K
-intensity ratios have also been measured. This information is used to deduce the defect configuration of the atoms. The mechanisms responsible for the multiple vacancy production are discussed. 相似文献