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1.
In this Note, we use Connes' theory of spectral triples to provide a connection between Manin's model of the dual graph of the fiber at infinity of an Arakelov surface and the cohomology of the mapping cone of the local monodromy. To cite this article: C. Consani, M. Marcolli, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 779–784. 相似文献
2.
The influence of the well width fluctuations on the dependence of the binding energy of excitonic complexes in quantum wells is studied by using the path-integral Monte-Carlo technique. The results are compared with available experimental data and a good agreement is found.Postdoctoral researcher of FWO-Vlaanderen 相似文献
3.
The effects of the organometallic compounds Bu2Sn-D -(?;)sorbitol, Bu2Sn-D -(+)glucose, Bu2Sn-D -(?)fructose and Bu2Sn-D -(+)glyceraldehyde were tested in vivo on different stages of Ascidian development, larval movement and metamorphosis. Organotin(IV) complexes are organometallic compounds widely used as industrial biocides, antifouling agents and agricultural fungicides and are toxic to a range of organisms. Two-cell stage embryos, if incubated for one hour in the organotin (IV) solutions, stopped the cleavage, which was restored when they were transferred into normal sea water. The gastrula stage was seriously affected in 10?4mol dm?3 solutions of the above-mentioned complexes: 85% of the embryos were anomalous neurulae with open neural folds, 5% were twisted larvae. The gastrulae, when incubated for 1 h in 10?5mol dm?3 solutions, developed twisted larvae in ovular envelopes and immobile larvae with twisted tails. Larvae treated with 10?4mol dm?3 and 10?5 mol dm?3 Bu2Sn-D -(?)sorbitol, Bu2Sn-D -(+)glucose and Bu2Sn-D -(+)glyceraldehyde solutions stopped swimming, did not metamorphose and afterwards underwent cytolysis. An initial hyperactivity of circular movements, followed by immobility, was observed in the larvae incubated in Bu2Sn-D -(?;)fructose. 相似文献
4.
R. Riva J. Rieger R. Jrme PH. Lecomte 《Journal of polymer science. Part A, Polymer chemistry》2006,44(20):6015-6024
This paper aims at reporting on the synthesis of a heterograft copolymer by combining the “grafting onto” process based on atom transfer radical addition (ATRA) and the “grafting from” process by atom transfer radical polymerization (ATRP). The statistical copolymerization of ε‐caprolactone (εCL) and α‐chloro‐ε‐caprolactone (αClεCL) was initiated by 2,2‐dibutyl‐2‐stanna‐1,3‐dioxepane (DSDOP), followed by ATRA of parts of the chlorinated units of poly(αClεCL‐co‐εCL) on the terminal double bond of α‐MeO,ω‐CH2?CH? CH2? CO2‐poly(ethylene oxide) (PEO). The amphiphilic poly(εCL‐g‐EO) graft copolymer collected at this stage forms micelles as supported by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The unreacted pendant chloro groups of poly(εCL‐g‐EO) were used to initiate the ATRP of styrene with formation of copolymer with two populations of randomly distributed grafts, that is PEO and polystyrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6015–6024, 2006 相似文献
5.
Summary Three types of polychloroprene rubbers (Du Pont de Nemours Co. Neoprenes AD, WHV and W) used for adhesives and having different crystallization rates have been investigated.The mechanical properties of the Neoprenes samples were determined and the films were examined under stretching by SAXS for a preliminary investigation on their different superreticular order.
Zusammenfassung Drei Typen von Polychloropren-Kautschuk mit verschiedener Kristallisationsgeschwindigkeit (Neoprene AD, WHV und W von Du Pont de Nemours), die als Klebemittel dienen, wurden als gedehnte Filme mechanisch und röntgenographisch (SAXS) untersucht. Sie zeigen Unterschiede in der Überstruktur.相似文献
6.
Roberto Cammi Caterina Ghio Jacopo Tomasi 《International journal of quantum chemistry》1986,29(3):527-539
The interaction of some neutral acids of π type, bearing appropriate unsymmetrical substitutions at the C?C group with some selected bases (H2O, NH3, OH?), is compared with that of the parent compound of a new set of neutral π acids, bearing symmetrical substitutions at the C?C group with the same bases. The analyses of the interaction energy, performed according to two decomposition schemes, with and without the counterpoise corrections, make clear the similarity of symmetrically and unsymmetrically substituted neutral organic acids. 相似文献
7.
Caterina Sartori 《manuscripta mathematica》1982,38(2):225-238
We present an asymptotic analysis for the solution of period 4 of
, where f is an odd function and a positive parameter.This work was supported by a C.N.R. fellowship during the period in which the author was visiting Rutgers University. 相似文献
8.
Caterina Canovaro Irene Calliari Michele Asolati Francesco Grazzi Antonella Scherillo 《Applied Physics A: Materials Science & Processing》2013,112(4):1019-1025
Mixing of different organic charge-transfer-complexes (CT-complexes) might allow the adjustment of the optical and morphological properties of the resulting material system. In this work, a study of two CT-complexes, mixed by thermal coevaporation at different concentrations by substituting only the acceptor molecules, is presented. Electron diffraction patterns, which were collected on samples of the ternary system of the prototypical CT-complexes DBTTF-TCNQ and DBTTF-F4TCNQ do not show any indication of a mixed crystalline phase or novel crystalline order. X-ray diffraction measurements additionally confirm the phase separation in the ternary system. However, upon mixing of the complexes, the degree of crystallinity of the individual phases is reduced. This effect correlates with the mixing ratio of the CT-complexes in the ternary compound. Furthermore, we do not observe a shift or the appearance of new peaks in the infrared spectra of (DBTTF-TCNQ) x :(DBTTF-F4TCNQ)1?x . Hence, there is no indication for a pronounced or novel chemical interaction between the individual CT-complexes in the mixed compound. 相似文献
9.
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