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31.
Konstantin Karaghiosoff Prof. Dr. Thomas M. Klapötke Prof. Dr. Carles Miró Sabaté Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(5):1164-1176
Methylation of 5-amino-1H-tetrazole ( 1 ) gives 1-methyl-5-amino-1H-tetrazole ( 2 ) and 2-methyl-5-amino-1H-tetrazole ( 3 ). A new family of energetic silver complexes based on ligands 1 , 2 and 3 with perchlorate and nitrate anions ( 10 – 15 ) were synthesized and characterized by using IR, Raman, and NMR (1H, 13C, 14N, and 35Cl NMR) spectroscopy, elemental analysis, and mass spectrometry. The crystal structures of the compounds were determined where possible and reveal interesting structural details that are discussed herein. Additionally, differential scanning calorimetry was used to assess the thermal stability of the new salts, which showed excellent thermal stabilities at temperatures up to and above 225 °C. Standard tests were also used to assess the sensitivity of the materials towards impact and friction. All the silver complexes showed increased sensitivity values in comparison with analogous protonated 5-amino-1H-tetrazolium perchlorate and nitrate salts. Some of these materials have sensitivity values that are comparable to commonly used primary explosives and all of them either deflagrate ( 12 – 14 ) or detonate loudly ( 10 and 11 ) on contact with an open flame. Lastly, nitrate salt 11 is easily initiated by thermal shock. It shows reasonably low sensitivity in comparison with other silver salts (e.g., silver azide or silver fulminate), which makes handling it much less hazardous. Compound 11 also has good thermal stability, decomposing at ≈300 °C, and shows interesting properties as a more environmentally benign alternative to lead(II) diazide in initiation devices for civil and military applications. 相似文献
32.
Sergio A. Moya Juana Gajardo Juan C. Araya Jaime J. Cornejo Véronique Guerchais Hubert Le Bozec J. Carles Bayón Alvaro J. Pardey Pedro Aguirre 《应用有机金属化学》2008,22(8):471-478
Novel ruthenium (II) complexes were prepared containing 2‐phenyl‐1,8‐naphthyridine derivatives. The coordination modes of these ligands were modified by addition of coordinating solvents such as water into the ethanolic reaction media. Under these conditions 1,8‐naphthyridine (napy) moieties act as monodentade ligands forming unusual [Ru(CO)2Cl2(η1‐2‐phenyl‐1,8‐naphthyridine‐ kN )(η1‐2‐phenyl‐1,8‐naphthyridine‐kN′)] complexes. The reaction was reproducible when different 2‐phenyl‐1,8‐naphthyridine derivatives were used. On the other hand, when dry ethanol was used as the solvent we obtained complexes with napy moieties acting as a chelating ligand. The structures proposed for these complexes were supported by NMR spectra, and the presence of two ligands in the [Ru(CO)2Cl2(η1‐2‐phenyl‐1,8‐naphthyridine‐ kN )(η1‐2‐phenyl‐1,8‐naphthyridine‐kN′)] type complexes was confirmed using elemental analysis. All complexes were tested as catalysts in the hydroformylation of styrene showing moderate activity in N,N′‐dimethylformamide. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
33.
Single–valued solutions for the case of two-sided market games without product differentiation, also known as Böhm–Bawerk horse market games, are analyzed. The nucleolus is proved to coincide with the τ value, and is thus the midpoint of the core. The Shapley value is in the core only if the game is a square glove market, and in this case also coincides with the two aforementioned solutions.Institutional support from research grants BEC 2002-00642, FEDER and SGR2001-0029 is gratefully acknowledged 相似文献
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37.
Miró P Pierrefixe S Gicquel M Gil A Bo C 《Journal of the American Chemical Society》2010,132(50):17787-17794
Uranyl-peroxide nanoclusters display different topologies based on square, pentagonal and hexagonal building blocks. Computed complexation energies of different cations (Li(+), Na(+), K(+), Rb(+), and Cs(+)) with [UO(2)(O(2))(H(2)O)](n) (n = 4, 5, and 6) macrocycles suggest a strong cation templating effect. The inherent bent structure of a U-O(2)-U model dimer is demonstrated and justified through the analysis of its electronic structure, as well as of the inherent curvature of the four-, five-, and six-uranyl macrocyles. The curvature is enhaced by cation coordination, which is suggested to be the driving force for the self-assembly of the nanocapsules. 相似文献
38.
We consider the propagation of wave packets for the nonlinear Schrödinger equation, in the semi-classical limit. We establish the existence of a critical size for the initial data, in terms of the Planck constant: if the initial data are too small, the nonlinearity is negligible up to the Ehrenfest time. If the initial data have the critical size, then at leading order the wave function propagates like a coherent state whose envelope is given by a nonlinear equation, up to a time of the same order as the Ehrenfest time. We also prove a nonlinear superposition principle for these nonlinear wave packets. 相似文献
39.
H. Pizzala M. Carles W. E. E. Stone A. Thevand 《Journal of Molecular Structure》2000,526(1-3):261-268
The crystal structure of the N-(3-hydroxysalicylidene)-4-methoxyaniline has been studied by single-crystal X-ray diffraction and solid-state NMR spectroscopy. This is the first example of a Schiff base derived from 3-hydroxysalicylaldehyde which displays in the asymmetric unit, four distinct molecules linked together in the crystal lattice by two types of intermolecular O–HO hydrogen bonds and formed by two independent tetramers. The 13C CPMAS NMR study corroborates the above results; the presence of different tautomeric equilibria in the same crystal structure is demonstrated and a qualitative estimation of the equilibrium mixture composition is given. 相似文献
40.
Sergio Peris Bartosz Tylkowski Joan Carles Ronda Ricard Garcia‐Valls José Antonio Reina Marta Giamberini 《Journal of polymer science. Part A, Polymer chemistry》2009,47(20):5426-5436
Two new polyethers, bearing azobenzene moiety in the side chain, were synthesized in excellent yields by means of anionic polymerization of 4‐glycidyloxyazobenzene and 4‐cyano‐4′‐glycidyloxyazobenzene (leading to azo‐P1 and azo‐P2 polymers, respectively) with the system polyiminophosphazene base t‐Bu‐P4/3,5‐di‐tert‐butylphenol as initiator. The polymers were characterized with respect to their molecular weights, structure, and calorimetric features. The polyether bearing cyanoazobenzene group in the side chain was found to exhibit nematic phase up to 200 °C. E–Z isomerization of both polymers in tetrahydrofuran solution, after irradiating with UV light at 364 nm for 15 min, was investigated by means of UV–visible absorption spectroscopy. In the case of glycidylic monomers as well as the resulting polymers, E–Z isomerization was also investigated by means of 1H NMR, by direct irradiation in the NMR probe in deuterated 1,1,2,2‐tetrachloroethane solution. By this technique, in the case of 4‐cyano‐4′‐glycidyloxyazobenzene, it was found that irradiation led to a photostationary state corresponding to an amount of Z isomer equal to 25%. For azo‐P1 polymer, Z–E or “reverse” isomerization was investigated at 60, 70, or 80 °C directly in the NMR probe; as expected, the process followed a first‐order rate law. The kinetic constants as well as the activation energy for the process were determined in this temperature range. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5426–5436, 2009 相似文献