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41.
Hossini I Harrad MA Ait Ali M El Firdoussi L Karim A Valerga P Puerta MC 《Molecules (Basel, Switzerland)》2011,16(7):5886-5895
Friedel-Craft acylation at 100 °C of 2,5,9,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocycloheptene [ar-himachalene], a sesquiterpenic hydrocarbon obtained by catalytic dehydrogenation of α-, β- and γ-himachalenes, produces a mixture of two compounds: (3,5,5,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-2-yl)-ethanone (2, in 69% yield), with a conserved reactant backbone, and 3, with a different skeleton, in 21% yield. The crystal structure of 3 reveals it to be 1-(8-ethyl-8-hydroperoxy-3,5,5-trimethyl-5,6,7,8-tetrahydronaphthalen-2-yl)-ethanone. In this compound O-H…O bonds form dimers. These hydrogen-bonds, in conjunction with weaker C-H…O interactions, form a more extended supramolecular arrangement in the crystal. 相似文献
42.
Harrad MA Valerga P Puerta MC Houssini I Ali MA El Firdoussi L Karim A 《Molecules (Basel, Switzerland)》2011,16(1):367-372
A recyclable catalyst, Ni(0)-CMC-Na, composed of nickel colloids dispersed in a water soluble bioorganic polymer, sodium carboxymethylcellulose (CMC-Na), was synthesized by a simple procedure from readily available reagents. The catalyst thus obtained is stable and highly active in alkene hydrogenations. 相似文献
43.
The dual fluorescence of para-N,N-dimethylaminobenzonitrile is observed for the first time in a rigid matrix at room temperature (polyvinylalcohol). A relationship between the twisted internal charge transfer (TICT) fluorescence and the formation of a ground-state hydrogen bonded complex is shown. 相似文献
44.
Reactions of Cu I salts with 1,4,5,8,9,12-hexaazatriphenylene (HAT) afford three types of cationic coordination polymers depending on the anion present in the reaction solution. In the crystal structure of {[Cu(HAT)][BF4]x1/3(C6H6)}infinity, (1), Cu ions and HAT molecules form extended layers that are best described as strongly distorted honeycomb nets. The space between the layers is occupied by [BF4]- anions and solvent molecules. {[Cu(HAT)][PF6]}infinity, (2), crystallizes as a chiral (10,3)-a net with [PF6]- anions residing in the cavities of the three-dimensional metal-organic framework. The crystal structure of {[Cu4(HAT)3][SbF6]4x3C6H6}infinity, (3), is based on unique extended [Cu4(HAT)3]infinity "nanotubules" filled with solvent molecules and [SbF6]- anions. 相似文献
45.
Kang M Chouai A Chifotides HT Dunbar KR 《Angewandte Chemie (International ed. in English)》2006,45(37):6148-6151
46.
47.
Abdellatif Moudafi 《Applied Mathematics Letters》2010,23(5):620-624
The aim of this paper is to investigate the asymptotic behavior of an inertial alternating algorithm based on the composition of resolvents of monotone operators. The proposed algorithm is a generalization of those proposed in Attouch et al. (2007) [3] and Bauschke et al. (2005) [1]. As a special case, we also recover the classical alternating minimization algorithm (Acker, 1980) [2], which itself is a natural extension of the alternating projection algorithm of von Neumann (1950) [4]. An application to equilibrium problems is also proposed. 相似文献
48.
The aim of this paper is to analyze the heat semigroup ${(\mathcal{N}_{t})_{t >0 } = \{e^{t \Delta}\}_{t >0 }}$ generated by the usual Laplacian operator Δ on ${\mathbb{R}^{d}}$ equipped with the d-dimensional Lebesgue measure. We obtain and study, via a method involving some semigroup techniques, a large family of functional inequalities that does not exist in the literature and with the local Poincaré and reverse local Poincaré inequalities as particular cases. As a consequence, we establish in parallel a new functional and integral inequality related to the Ornstein–Uhlenbeck semigroup. 相似文献
49.
50.
Youssef Ait Ahmed Ahmed Tirbiyine Ahmed Taoufik Hassan El Ouaddi Habiba El Hamidi Abdelhalim Hafid 《Phase Transitions》2013,86(11):1093-1099
ABSTRACTWe have studied the reversible and irreversible part of the hysteresis loops as a function of slow cooling rate through the order–disorder transformation near 80?K for the deuterated (κ-D8-Br) κ-(BEDT-TTF)2Cu[N(CN)2]Br organic superconductor. We estimated the critical current density JC and the thermodynamic critical field HC from the magnetic hysteresis loops. Temperature dependence of the critical current density derived from the irreversible part using Bean’s model. The thermodynamic critical field HC has been obtained from the reversible part of the hysteresis loops. 相似文献