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91.
92.
Adolfo V. T. Cartaxo Jo o L. Rebola Nata a B. Pavlovi Pedro M. A. Charrua Daniel D. T. Fonseca Jos A. P. Morgado Ruben S. Luí s M rio R. G. Leiria 《Fiber and Integrated Optics》2005,24(3):331-352
This article introduces the main achievements resulting from the DWDM/ODC project. The five areas of research activity within the DWDM/ODC project cover some of the main issues of design and development of dense wavelength division multiplexing systems for transparent optical networks. These issues are: performance assessment with arbitrary optical filtering; performance of signaling formats; dispersion compensation strategies for directly and externally modulated systems in presence of nonlinear transmission-induced degradation; and the impact of noise and crosstalk in the extent of transparent optical networks. All five areas of research activity have contributed significantly to a better understanding of the limitations present in dense wavelength division multiplexing systems. 相似文献
93.
C. Romeike M. R. Wegewijs W. Wenzel M. Ruben H. Schoeller 《International journal of quantum chemistry》2006,106(4):994-1000
We investigate the magnetic state of a recently synthesized [2 × 2]‐metal‐organic grid complex as a function of its redox state. Our analysis of a phenomenological model for the relevant molecular orbitals reveals that additional electrons on the ligands can couple their spins via the bridging metal sites. We find that at certain stages of the reduction of the complex cation, a maximal total spin ground state of the complex (S = 3/2) can be stabilized by the Nagaoka mechanism. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 相似文献
94.
Ruben Mercadé‐Prieto William R. Paterson D. Ian Wilson 《Journal of Polymer Science.Polymer Physics》2008,46(11):1007-1021
The dissolution behavior of heat‐induced whey protein gels in alkali is compared with the literature on the dissolution of (1) uncrosslinked synthetic polymers with chemical reaction, (2) uncrosslinked polymers in a good solvent, and (3) crosslinked hydrogels. Diffusion of hydroxide and acid–base reactions, which are key processes in the dissolution of phenolic resins in alkali (Case 1), are found not to be very important with protein gels. The strong dependency of the dissolution rate on the free volume observed in protein gels is described by a large scaling factor, as predicted for Case 2 theory, indicating that the disentanglement of long chains before they are released is important. The cleavage of intermolecular crosslinks, which is important in Case 3, is also identified as a key dissolution step, where the complexity of protein chemistry comes into play. Synthetic polymer mechanisms are therefore able to elucidate several aspects of protein gel dissolution, but are not yet sufficient to explain all aspects of the process. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1007–1021, 2008 相似文献
95.
96.
Charles A. Jones Amy Zweber James P. DeYoung. James B. McClain Ruben Carbonell Joseph M. DeSimone 《固体与材料科学评论》2004,29(3-4):97-109
Condensed carbon dioxide (CO2) has emerged as a leading enabler of advanced semiconductor manufacturing processes. By exploiting the physical properties of CO2, some of the current challenges encountered in microelectronics processing related to shrinking feature sizes and materials compatibility have been addressed. Furthermore, the potential for reduction of chemicals used in processing is realized. Applications of CO2 in microelectronics operations such as wafer cleaning, spin-coating, development, and stripping of photoresists, drying, low-k film preparation and repair, etching, and metal deposition are discussed. 相似文献
97.
Ribicki Ariane Caroline Chemin Bianca Gurski Van Haandel Viviane Jandira Winiarski João Paulo de Castro Rozada Thiago Pessoa Christiana Andrade Estrada Ruben Auccaise Fiorin Barbara Celânia Fujiwara Sérgio Toshio 《Journal of Sol-Gel Science and Technology》2018,87(1):216-229
Journal of Sol-Gel Science and Technology - A silsesquioxane based on a silica matrix and 4-(aminomethyl)pyridine group was successfully synthesized using the sol–gel process with the... 相似文献
98.
99.
Tetrahedral n-type materials: efficient quenching of the excitation of p-type polymers in amorphous films 总被引:1,自引:0,他引:1
Ganesan P Yang X Loos J Savenije TJ Abellon RD Zuilhof H Sudhölter EJ 《Journal of the American Chemical Society》2005,127(42):14530-14531
Tetrahedral naphthalenediimide compound 1 has been synthesized as an example of a new class of amorphous n-type materials, in which the nondirectionality obtained by its shape is decoupled from its optoelectronic properties. 1 forms bicontinuous films with p-type polymers and effectively quenches the excited state, yielding long-lived mobile charge carriers on pulsed illumination. 相似文献
100.
Ruben M Ziener U Lehn JM Ksenofontov V Gütlich P Vaughan GB 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,11(1):94-100
Hierarchical self-assembly of complex supramolecular architectures allows for the emergence of novel properties at each level of complexity. The reaction of the ligand components A and B with Fe(II) cations generates the [2x2] grid-type functional building modules 1 and 2, presenting spin-transition properties and preorganizing an array of coordination sites that sets the stage for a second assembly step. Indeed, binding of La(III) ions to 1 and of Ag(I) ions to 2 leads to a 1D columnar superstructure 3 and to a wall-like 2D layer 4, respectively, with concomitant modulation of the magnetic properties of 1 and 2. Thus, to each of the two levels of structural complexity generated by the two sequential self-assembly steps corresponds the emergence of novel functional features. 相似文献