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991.
Susan Jacob Melodie L. Schmitt Mark E. Schlesinger 《Journal of Thermal Analysis and Calorimetry》2010,100(3):897-900
High-temperature differential scanning calorimetry was used to investigate the thermodynamic parameters of the γ–β and β–α transitions in calcium pyrophosphate (Ca2P2O7). The measured enthalpy of transition compared well with previous results when higher heating rates (≥20 K min?1) were used. Recommendations for optimal use of HTDSC in high-temperature phase transition measurements are presented. 相似文献
992.
Stefan Eibl Andrew Fitch Michela Brunelli Alexander Dominic Evans Philip Pattison Marie Plazanet Mark Robert Johnson Christiane Alba‐Simionesco Helmut Schober 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(6):o278-o280
The title compound, C10H18, a decalin stereoisomer, crystallizes with Z′ = 0.5 in the space group P21/n. The trans‐decalin molecule is located on an inversion centre with both rings in a chair conformation, making for a quasi‐flat overall shape. Despite the absence of hydrogen bonds, it crystallizes easily. In this work the unknown crystal structure of trans‐decalin has been solved and refined using X‐ray powder diffraction data. 相似文献
993.
Jeff T. Gostick Marios A. Ioannidis Michael W. Fowler Mark D. Pritzker 《Electrochemistry communications》2009,11(3):576-579
The condition of liquid water breakthrough at the cathode of polymer electrolyte fuel cells (PEMFC) is studied experimentally and data on corresponding water saturation and capillary pressure are provided for gas diffusion layers (GDL) with and without a microporous layer (MPL). The data demonstrate that the GDL saturation at water breakthrough is drastically reduced from ca. 25% to ca. 5% in the presence of MPL. This observation is consistent with considerations of invasion percolation in finite-size lattices and suggests an explanation for the role of MPL in improving PEMFC performance at high current densities. 相似文献
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Mark Elin Simeon Reich David Shoikhet Fiana Yacobzon 《Complex Analysis and Operator Theory》2008,2(1):55-86
We study the asymptotic behavior of one-parameter continuous semigroups of holomorphic mappings. We present angular characteristics
of their trajectories at their Denjoy–Wolff points, as well as at their regular repelling points (whenever they exist). This
enables us to establish new rigidity properties of holomorphic generators via the asymptotic behavior of the semigroups they
generate.
Received: May 11, 2007. Accepted: July 22, 2007. 相似文献
1000.
Mindaugas Radziunas Vasile Z. Tronciu Uwe Bandelow Mark Lichtner Martin Spreemann Hans Wenzel 《Optical and Quantum Electronics》2008,40(14-15):1103-1109
Theoretical and experimental investigations have been carried out to study the spectral and spatial behavior of monolithically integrated distributed-feedback tapered master-oscillators power-amplifiers emitting around 973 nm. Introduction of self and cross heating effects and the analysis of longitudinal optical modes allows us to explain experimental results. The results show a good qualitative agreement between measured and calculated characteristics. 相似文献