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101.
Glauco Battagliarin Sreenivasa Reddy Puniredd Sebastian Stappert Wojciech Zajaczkowski Suhao Wang Chen Li Wojciech Pisula Klaus Müllen 《Advanced functional materials》2014,24(47):7530-7537
In this paper n‐type semiconductors synthesized via selective fourfold cyanation of the ortho‐ and bay‐positions (2,5,10,13‐ and 1,6,9,14‐positions respectively) of teyrrylenediimides are reported. A detailed study about the impact of the diverse functionalization topologies on the optoelectronic properties, self‐organization from solution, solid‐state packing, and charge carrier transport in field‐effect transistors is presented. The ortho‐substitution preserves the planarity of the core and favors high order in solution processed films. However, the strong intermolecular interactions lead to a microstructure with large aggregates and pronounced grain boundaries which lower the charge carrier transport in transistors. In contrast, the well‐soluble bay‐functionalized terrylenediimide forms only disordered films which surprisingly result in n‐type average mobilities of 0.17 cm2/Vs after drop‐casting with similar values in air. Processing by solvent vapor diffusion enhances the transport to 0.65 cm2/Vs by slight improvement of the order and surface arrangement of the molecules. This mobility is comparable to highest n‐type conductivities measured for solution processed PDI derivatives demonstrating the high potential of TDI‐based semiconductors. 相似文献
102.
Wojciech Ciesielski & Piotr Tomasik 《International Journal of Food Science & Technology》2004,39(6):691-698
It was shown that potato starch formed Werner‐type complexes. In these complexes a metal atom is ligated by the lone electron pairs of hydroxyl groups from d ‐glucose units and phosphate groups in starch. Acetate, chloride and nitrate were counter‐ions to the transition metal atoms. The metal cations bound preferentially to the phosphoric acid moiety of amylopectin, but secondarily they were co‐ordinated by the hydroxyl groups of the d ‐glucose units. This resulted in the formation of clathrate cages in which a significant number of the water molecules were trapped. Such structures were able to co‐ordinate further metal cations. Only Mn(II) and Co(II) ions, with acetate counter‐ions, neither formed clathrate cages nor were co‐ordinated by the hydroxyl groups of the d ‐glucose of starch. 相似文献
103.
Zenon Foltynowicz Wojciech Kozak Ryszard Fiedorow 《Packaging Technology and Science》2002,15(2):75-81
Temperature‐programmed reduction (TPR) measurements were performed for iron oxalates, iron(III) hydroxide (both pure and with additives) and iron(II, III) oxide. On the ground of TPR curves, reduction temperatures of the iron‐containing parent substances were chosen followed by oxygen uptake determination. Comparison of oxygen uptakes points to the use of Fe(OH)3 and Fe3O4 as more advantageous than that of iron oxalates. Co‐precipitation from a mixed solution of iron and manganese salts results in a product which is more resistant to particle agglomeration at elevated temperatures than that obtained byprecipitation from solution of iron salt alone. Copyright © 2002 JohnWiley & Sons, Ltd. 相似文献
104.
Andrzej Kreft Edward Chrus̀ciel Bohdan Dziunikowski Jan Gyurcsak Stefan Kalita Andrzej Lenda Wojciech Przybylowicz Jan Woźniak 《Fuel》1984,63(9):1281-1284
A method for the simultaneous determination of calorific value Qr, ash yieldAr and total water content Wrt of soft brown coals is described. The method involves instrumental analysis of brown coal samples using neutron thermalization and gamma back-scattering techniques. Over 80 coal samples (1.1 kg) were analysed, having Qrvalues up to 15.5 MJ kg?1,Ar ranging from 3.6 to 76.1 wt% and Wrt ranging from 11.4 to 61.7 wt%. A comparison of the results from the instrumental method with those of standard laboratory analyses is given, followed by a discussion of the accuracy of the method and of possible ways for improving it. 相似文献
105.
Tomasz Czeppe Wojciech Zakulski Elbieta Bielaska 《Journal of Phase Equilibria and Diffusion》2003,24(3):249-254
A part of the Al-Mg phase diagram was studied in the range of composition between 48 and 61 at.% Al by DSC and SEM/EDS methods.
The temperature ranges of stability of the β, γ, and ɛ phases were considered. It was found that the congruent melting temperature
of the β phase was 450±1 °C. The Al content in that phase was determined to be 61±1 at.% Al at 420 °C. The upper temperature
limit of the stability of the ɛ phase was established to be 427±1 °C. The Al content changed from 54 at.% at 390 °C to 56
at.% at 420 °C. The lower temperature limit of the ɛ phase formation was not determined, as a result of a slow ɛ=β+γ reaction.
The hypothetical λ or ζ phases were not found, but it was observed that decomposition of oxides might produce extra thermal
effects. 相似文献
106.
Determination of the ash yield and the mineral matter content of brown coals by density measurements
Edward Chruściel Wit Jagusztyn Andrzej Kreft Andrzej Lenda Wojciech Przybylowicz Jan Woźniak 《Fuel》1983,62(3):389-390
A method of measuring the density of bed-moist brown coals based on their plastic properties is described and the feasibility of using the method for determination of the ash yield of the coal is evaluated. 相似文献
107.
108.
Wojciech Pietraszkiewicz Janusz Badur 《International Journal of Engineering Science》1983,21(9):1097-1115
Finite rotations in continuum mechanics are described by means of either a proper orthogonal tensor or finite rotation vectors. Some algebraic relations concerning the finite rotations are reviewed. Formulae expressing them in terms of displacements are given. Along each of the curvilinear coordinate lines the finite rotations are shown to satisfy some systems of the linear first-order differential equations. Each system of the equations is presented in four different but equivalent forms associated with an intermediate stretched basis or with an intermediate rotated basis. Integrability conditions of the system of equations provide various alternative forms of compatibility conditions in continuum mechanics. The displacement field is expressed through the stretch and rotation fields in the form of three successive line integrals. The formula describes the displacements to within a constant finite translation and a constant finite rotation. The procedure proposed here generalizes the formula derived by Cesàro (1906) within the classical linear theory of elasticity. 相似文献
109.
110.
Marta Legawiec-Jarzyna Wojciech Juszczyk Magdalena Bonarowska Zbigniew Kaszkur Leszek Kępiński Zbigniew Kowalczyk Zbigniew Karpiński 《Topics in Catalysis》2009,52(8):1037-1043
A series of Pt/Al2O3 catalysts were prepared by the impregnation method and were characterized by TEM, XRD, H2 and CO chemisorptions, and investigated in the hydrodechlorination of tetrachloromethane. Three Pt-rich, Pt–Au/Al2O3 catalysts (Pt100, Pt95Au5 and Pt90Au10) showed a similar metal particle size (~2.5–2.7 nm), so observed changes in the catalytic behavior are ascribed to alloying
effect, especially because a considerable degree of Pt–Au mixing was achieved in the bimetallic samples. It appeared that
by introducing very small amount of gold (10 at.%) to platinum, the catalytic activity is increased. It is argued that the
occurrence of this moderate synergistic effect is associated with a decreased tendency of surface chloriding when platinum
is alloyed with gold.
Zbigniew Kowalczyk—deceased. 相似文献