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941.
We characterize lattices obtained from another lattice by a doubling of a convex set. This gives rise to a characterization of the class CN of lattices obtained by doublings of connected and convex sets when starting from a two-element lattice, and from this characterization result we derive an efficient recognition algorithm. This algorithm can be directly applied to the recognition of lattices in the subclasses of CN defined by giving some additionnal constraints on the convex sets used in the doublings. 相似文献
942.
Stéphanie Brouillet-Fourmann Christian Carrot Nathalie Mignard 《Rheologica Acta》2003,42(1-2):110-117
The structural evolution of a maize flour was followed by means of oscillatory shear measurements during heating at a rate
of 10 °C/min in presence of water. These measurements were performed in a special plate and plate vessel designed to prevent
moisture loss. The phenomena of gelatinization and gelation were clearly identified and their connection with the moisture
content also demonstrated. Moreover, the complex mechanisms involved in gelatinization and gelation in native starch were
separated. Softening of the amylose zones, exchange of water and amylose within the starch granules followed by amylopectin
melting leads to the gelation of starch. 相似文献
943.
This Note proposes a new methodology for function classification with Support Vector Machine (SVM). Rather than relying on projection on a truncated Hilbert basis as in our previous work, we use an implicit spline interpolation that allows us to compute SVM on the derivatives of the studied functions. To that end, we propose a kernel defined directly on the discretizations of the observed functions. We show that this method is universally consistent. To cite this article: N. Villa, F. Rossi, C. R. Acad. Sci. Paris, Ser. I 343 (2006). 相似文献
944.
Nathalie LHermite Jean-Franois Peyrat Moud Alami Jean-Daniel Brion 《Tetrahedron letters》2005,46(52):8987-8991
A rapid convergent synthesis of first- and second-generation halogenated linear poly(arylpropargyl ether) branches 7 and 10 is described. The key step of the sequence studied involves a selective Sonogashira–Linstrumelle (S–L) cross-coupling reaction of aryl iodides with alkynes bearing an sp2-carbon–iodine bond. Application to the synthesis of functionalized first-generation poly(arylpropargylether) stars having a benzene-1,3,5-tricarboxylic acid core has been realized. 相似文献
945.
Nathalie Bellec Frédéric Lerouge Olivier Jeannin Geneviève Cerveau Robert J.P. Corriu Dominique Lorcy 《Journal of organometallic chemistry》2006,691(26):5774-5781
The effect of the interactions generated by the spacer group between the TTF core and the four triethoxysilane groups on the auto-organization of the organic bridging moieties in hybrid materials obtained by sol-gel chemistry has been investigated. The silica-based hybrid solids are highly polycondensed. They present different scales of organization (nanometric and micrometric) that are independent one from each other and are governed by the different parameters which control the kinetics of polycondensation. Their anisotropic organization is function of the interaction forces induced by the spacer, van der Waals, hydrogen bonding or both, during the hydrolytic condensation process. 相似文献
946.
947.
Theoretical and Experimental Study on Boron β‐Diketonate Complexes with Intense Two‐Photon‐Induced Fluorescence in Solution and in the Solid State 下载免费PDF全文
Dr. Pierre‐Henri Lanoë Dr. Bastien Mettra Dr. Yuan Yuan Liao Dr. Nathalie Calin Dr. Anthony D'Aléo Tomotaka Namikawa Prof. Kenji Kamada Prof. Fréderic Fages Dr. Cyrille Monnereau Dr. Chantal Andraud 《Chemphyschem》2016,17(14):2128-2136
Three boron diketonate chromophores with extended π‐conjugated backbone were prepared and their spectroscopic features were investigated through a combined theoretical/experimental study. It was shown that these complexes, which undergo very large electronic reorganization upon photoexcitation, combine large two‐photon absorption cross section with an emission energy and quantum efficiency in solution that is strongly dependent on solvent polarity. The strong positive influence of boron complexation on the magnitude of the two‐photon absorption was clearly established, and it was shown that the two‐photon absorption properties were dominated by the quadrupolar term. For one of the synthesized compounds, intense one‐ and two‐photon‐induced solid‐state emission (fluorescence quantum yield of 0.65 with maximum wavelength of 610 nm) was obtained as a result of antiparallel J‐aggregate crystal packing. 相似文献
948.
Natalia Del Rio Dr. Antoine Baceiredo Dr. Nathalie Saffon‐Merceron Dr. Daisuke Hashizume M. Sc. Dennis Lutters Prof. Dr. Thomas Müller Dr. Tsuyoshi Kato 《Angewandte Chemie (International ed. in English)》2016,55(15):4753-4758
A new stable heterocyclic germylene, in which the divalent germanium atom lies between a nitrogen atom and a phosphanylidene phosphorane group, was synthesized. Experimental and theoretical studies revealed the peculiar effect of phosphanylidene phosphorane substituent, which is a stronger π‐donor towards germanium than an amino group is. Because of the weak phosphorus–germanium π‐bond, this new germylene compound shows an enhanced reactivity compared to classical N‐heterocyclic germylenes. 相似文献
949.
Donor‐Stabilized 1,3‐Disila‐2,4‐diazacyclobutadiene with a Nonbonded Si⋅⋅⋅Si Distance Compressed to a Si=Si Double Bond Length 下载免费PDF全文
Dr. David Gau Raphael Nougué Dr. Nathalie Saffon‐Merceron Dr. Antoine Baceiredo Dr. Abel De Cózar Prof. Fernando P. Cossío Dr. Daisuke Hashizume Dr. Tsuyoshi Kato 《Angewandte Chemie (International ed. in English)》2016,55(47):14673-14677
A donor‐stabilized 1,3‐disila‐2,4‐diazacyclobutadiene presents an exceptionally short nonbonded Si???Si distance (2.23 Å), which is as short as that of Si=Si bonds (2.15–2.23 Å). Theoretical investigations indicate that there is no bond between the two silicon atoms, and that the unusual geometry can be related to a significant coulomb repulsion between the two ring nitrogen atoms. This chemical pressure phenomenon could provide an alternative and superior way of squeezing out van der Waals space in highly strained structures, as compared to the classical physical methods. 相似文献
950.
Vandenbroucke Arne M. Aerts Robby Van Gaens Wouter De Geyter Nathalie Leys Christophe Morent Rino Bogaerts Annemie 《Plasma Chemistry and Plasma Processing》2015,35(1):217-230
Plasma Chemistry and Plasma Processing - In this work, we study the abatement of dilute trichloroethylene (TCE) in air with a negative direct current corona discharge. A numerical model is used to... 相似文献