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1.
Ahmed M. Mayouf Yong-Tae Park 《Journal of photochemistry and photobiology. A, Chemistry》2002,150(1-3):115-123
The UV photolysis of 2′-chloro-4-R-benzanilides in acetonitrile solution under nitrogen atmosphere leads to the formation of intramolecular photocyclization products (9-R-phenanthridin-6(5)-one, 20–30%), along with the minor photoreduction, photo-Fries, and intramolecular photosubstitution products. The photoreaction of 2′-chloro-4-R-benzanilide in acetonitrile solution containing 10% of water or aqueous sodium hydroxide however gives 2-(4-R-phenyl)-1,3-benzoxazole as a major product (30%) along with the photoreduction, photo-Fries and intramolecular photocyclization products. 相似文献
2.
Tarek Sellami 《Comptes Rendus Mathematique》2010,348(17-18):1005-1008
Any Pisot substitution can be associated with a bounded set with interesting properties, called the Rauzy fractal. This set is obtained by projection of the broken line associated with an infinite fixed point. Two substitutions having the same incidence matrix can have different Rauzy fractals. We show that under weak conditions, the intersection of these two fractals has strictly positive measure, and can also be generated by a substitution. 相似文献
3.
EMF versus Li-composition relation is determined by electrochemical insertion for Li-V5S8. The values of the thermodynamic functions ΔG, ΔH, ΔS corresponding to the lithium insertion reaction have been deduced. The Thompson method (electrochemical potential spectroscopy) has been applied to the V5S8 cathode, but it appears not valid in our case. The calculation of current versus time function is made to analyze the validity of this method. This technique requires: fast diffusion of Li in the host material, small grain size, small increments of applied voltage, low value of the cut-off current. 相似文献
4.
The properties of the solid solution VSe2?xSx 0 ? xnom ? 2 have been investigated for secondary battery application. The phase VSe2 is observed for 0 ? xnom ? 1.2 and the phase V5S8 is found using RX analysis for xnom >1.2. The amount of lithium chemically incorporated in this structure by reaction with n-butyllithium is 2 Li/vanadium for 0 ? xnom ? 0.8 and 1.4 Li/vanadium for V5S8. An electrochemical technique (galvanostatic) indicates that the amount of lithium incorporated depends on the xnom values, the grain size and the discharge rate. The best results are obtained for 0.2 ? xnom ? 0.6 (capacity = 164?172 Ah kg?1 and energy density = 385?465 Wh kg?1). 相似文献
5.
Abdellah Bahmani Mayouf Sellami Noureddine Bettahar 《Journal of Thermal Analysis and Calorimetry》2012,107(3):955-962
Bismuth mixed oxide powders were prepared by oxalate coprecipitation process. The thermal decomposition behaviour of the coprecipitate
precursors has been followed by thermal analysis (TG-DTA) and FTIR spectroscopy. During the decomposition of the precursor,
several intermediates species were detected and a mechanism of formation of mixed oxide by this method is proposed. After
the thermal treatment, the precursor obtained of suggested formula Ca3[Bi6O6(C2O4)4(OH)3NO3]0.5H2O, has led to the formation of CaBi2O4 at shorter reaction time than the traditional ceramic method. In order to consolidate the results, the coprecipitation in
absence of oxalic precipitant under the same conditions was examined. XRD and scanning electron spectroscopy were used to
study particles sizes and morphology. 相似文献
6.
The rate constant of formation, dissociation, and redox reaction of the benzyl radical-copper(II) ion complex have been determined at temperatures from 274 K to 333 K by laser flash photolysis of 1,3-diphenyl-2-propanone (DBK) in a 10% acetonitrile-90% water mixture containing copper(II)perchlorate. Rate constants were calculated from time resolved absorbances of both benzyl radicals (Bz) at 315 nm and benzyl-copper complexes (BzCu2+) at 375 nm. Values of the rate constants of the formation of BzCu2+ complex were fitted to the equation and the rate constant of the reverse reaction of BzCu2+ complex to the equation The rate constant of the redox reaction of BzCu2+ complex to benzyl alcohol and copper(I) ion can be described by the equation The first order rate constant of dissociation of phenylacetyl radical formed initially in the flash photolysis of DBK is given by the equation 相似文献
7.
Ahmed M. Mayouf Helge Lemmetyinen Jouko Koskikallio 《Journal of photochemistry and photobiology. A, Chemistry》1993,70(3):215-221
The self-termination rates of the benzyl radical (C6H5---CH2√) and para-substituted benzyl radicals (X---C6H4---CH2√) were studied in aqueous solutions. The Arrhenius parameters and activation energies were determined in the temperature range 275.5–328 K. The kinetic activation energies of these radicals were close to the dynamic activation energy of the solvent, indicating that the termination rate is controlled by diffusion. The values for the rate constants (2kt (109 dm3 mol−1 s−1)) and the activation energies (E (kJ mol−1)) were 5.94±0.52 and 14.69±0.61 for CH3O---C6H4---CH2√, 4.52±0.2 and 17.65±1.16 for CH37z.sbnd;C6H4---CH2√, 3.07±0.45 and 17.58±0.97 for H---C6H4---CH2√, 4.13±0.81 and 19.10±1.20 for Cl---C6H4---CH2√ and 4.17±0.44 and 14.62±0.52 for NO2---C6H4---CH2√. 相似文献
8.
9.
Implementation of a continuation method for normal maps 总被引:2,自引:0,他引:2
This paper presents an implementation of a nonsmooth continuation method of which the idea was originally put forward by Alexander
et al. We show how the method can be computationally implemented and present numerical results for variational inequality
problems in up to 96 variables.
The research reported here was sponsored by the Air Force Office of Scientific Research, Air Force Materiel Command, USAF,
under grant numbers F49620-93-1-0068 and F49620-95-1-0222, by the U.S. Army Research Office under grant number DAAH04-95-1-0149,
and by the National Science Foundation under grant number CCR-9109345. The U.S. Government has certain rights in this material,
and is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon.
The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing
the official policies or endorsements, either expressed or implied, of the sponsoring agencies or the U.S. Government. 相似文献
10.