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101.
Arsac F Bianchi D Chovelon JM Ferronato C Herrmann JM 《The journal of physical chemistry. A》2006,110(12):4202-4212
The present study concerns an experimental microkinetic approach of the photocatalytic oxidation (PCO) of isopropyl alcohol (IPA) into acetone on a pure anatase TiO2 solid according to a procedure previously developed. Mainly, the kinetic parameters of each surface elementary step of a plausible kinetic model of PCO of IPA are experimentally determined: natures and amounts of the adsorbed species and rate constants (preexponential factor and activation energy). The kinetics parameters are obtained by using experiments in the transient regime with either a FTIR or a mass spectrometer as a detector. The deep oxidation (CO2 and H2O formation) of low concentrations of organic pollutants in air is one of the interests of the PCO. For IPA, literature data strongly suggest that acetone is the single route to CO2 and H2O and this explains that the present study is dedicated to the elementary steps involving gaseous and adsorbed C3H(x)O species. The microkinetic study shows that strongly adsorbed IPA species (two species denoted nd-IPA(sads) and d-IPA(sads) due to non- and dissociative chemisorption of IPA, respectively) are involved in the PCO of IPA. A strong competitive chemisorption between IPA(sads) and a strongly adsorbed acetone species controls the high selectivity in acetone of the PCO at a high coverage of the surface by IPA(sads). The kinetic parameters of the elementary steps determined in the present study are used in part 2 to provide a modeling of macroscopic kinetic data such as the turnover frequency (TOF in s(-1)) of the PCO using IPA/O2 gas mixtures. 相似文献
102.
A polyhedron is integral if all its extreme points have 0, 1 components and in this case the matrix M is called ideal. When Q has fractional extreme points, there are different ways of classifying how far M is away from being ideal, through the polyhedral structure of Q. In this sense, Argiroffo, Bianchi and Nasini (2006) [1] defined a nonidealness index analogous to an imperfection index due to Gerke and McDiarmid (2001) [10].In this work we determine the nonidealness index of rank-ideal matrices (introduced by the authors (2008)). It is known that evaluating this index is NP-hard for any matrix. We provide a tractable way of evaluating it for most circulant matrices, whose blockers are a particular class of rank-ideal matrices, thereby following similar lines as done for the imperfection ratio of webs due to Coulonges, Pêcher and Wagler (2009) [7].Finally, exploiting the properties of this nonidealness index, we identify the facets of the set covering polyhedron of circulant matrices, having maximum strength with respect to the linear relaxation, according to a measure defined by Goemans (1995) [9]. 相似文献
103.
M. Bianchi 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(1):460-468
In this paper we introduce some notions of well-posedness for scalar equilibrium problems in complete metric spaces or in Banach spaces. As equilibrium problem is a common extension of optimization, saddle point and variational inequality problems, our definitions originates from the well-posedness concepts already introduced for these problems.We give sufficient conditions for two different kinds of well-posedness and show by means of counterexamples that these have no relationship in the general case. However, together with some additional assumptions, we show via Ekeland’s principle for bifunctions a link between them.Finally we discuss a parametric form of the equilibrium problem and introduce a well-posedness concept for it, which unifies the two different notions of well-posedness introduced in the first part. 相似文献
104.
In a letter to Born, Einstein wrote [42]: “Quantum mechanics is certainly imposing. But an inner voice tells me that it is not yet the real thing. The theory says a lot, but does not really bring us any closer to the secret of the ‘old one.’ I, at any rate, am convinced that He does not throw dice.” In this paper we take seriously Einstein’s famous metaphor, and show that we can gain considerable insight into quantum mechanics by doing something as simple as rolling dice. More precisely, we show how to perform measurements on a single die, to create typical quantum interference effects, and how to connect (entangle) two identical dice, to maximally violate Bell’s inequality. 相似文献
105.
D. Bianchi S. Yu. Dobrokhotov B. Tirozzi 《Russian Journal of Mathematical Physics》2008,15(4):427-446
In the present (second) part of the paper, we study the asymptotic behavior of the solution of the Cauchy problem for a nonhomogeneous
wave equation and also consider (instead of the wave equation) an equation with added fourth derivatives containing a small
parameter, i.e., include the effects of weak dispersion.
The research was supported by RFBR grant no. 08-01-00726 and by the scientific agreement between the Department of Physics
of the University of Rome “La Sapienza“ and the A. Ishlinski Institute for Problems in Mechanics of Russian Academy of Sciences,
Moscow. 相似文献
106.
107.
Arrahli Abdellah Kherbeche Abdelhak Bianchi Daniel 《Research on Chemical Intermediates》2019,45(3):1421-1436
Research on Chemical Intermediates - FTIR spectroscopy and volumetric measurements are used to study the adsorption of CO (mainly 1% CO/He) in the temperature range 300–713 K on a... 相似文献
108.
Bazzicalupi C Bencini A Bianchi A Borri C Danesi A Garcia-España E Giorgi C Valtancoli B 《The Journal of organic chemistry》2008,73(21):8286-8295
The interaction of the biologically relevant anions deriving from the six pyridinedicarboxylic acids (H2PDC) with two macrocyclic receptors containing a pentamine chain and a bipyridine (1) or a phenanthroline (2) moiety, as well as with the aliphatic analogue [21]aneN7 (3), was studied by means of spectroscopic methods (UV-vis, NMR) and potentiometric titrations affording the stability constants of the adducts formed. All three receptors form stable complexes with the substrates thanks to the formation of several salt bridges and hydrogen bond contacts, as observed in the crystal structure of the H8[3(2,6-PDC)4] x H2O x 0.5 EtOH solid compound. Additional pi-stacking interactions between the aromatic moieties of substrates and receptors enhance the stability of complexes with 1 and 2. Compounds 1 and 2 show a marked selectivity toward 2,6-pyridinedicarboxylate anions. In particular, 1 is able to perform a very efficient recognition of these species in the presence of 2 and 3. Molecular modeling calculations suggested that such recognition ability of 1 can be ascribed to a superior structural and electrostatic complementarity with the substrate compared to 2 and 3. 相似文献
109.
Dr. Pengfei Wu Prof. Dr. Adriana Pietropaolo Dr. Mariagrazia Fortino Dr. Masayoshi Bando Prof. Dr. Katsuhiro Maeda Dr. Tatsuya Nishimura Shuhei Shimoda Dr. Hiroyasu Sato Prof. Dr. Naofumi Naga Prof. Dr. Tamaki Nakano 《Angewandte Chemie (International ed. in English)》2023,62(29):e202305747
Optically active, hyperbranched, poly(fluorene-2,4,7-triylethene-1,2-diyl) [poly(fluorenevinylene)] derivatives bearing a neomenthyl group and a pentyl group at the 9-position of the fluorene backbone at various ratios acted as a chirality donor (host polymers) efficiently included naphthalene, anthracene, pyrene, 9-phenylanthracene, and 9,10-diphenyanthracene as a chirality acceptor (guest molecules) in their interior space in film as well as in solution, with the guest molecules exhibiting intense circular dichroism through chirality transfer with chirality amplification. The efficiency of the chirality transfer was much higher with higher-molar-mass polymers than lower-molar-mass ones as well as with hyperbranched polymers compared to the analogous linear ones. The hyperbranched polymers include the small molecules in their complex structure without any specific interactions at various stoichiometries. The included molecules may have ordered intermolecular arrangement that may be somewhat similar to those of liquid crystals. Naphthalene, anthracene, and pyrene included in the polymer exhibited efficient circularly polarized luminescence, where the chirality was remarkably amplified in excited states, and anthracene exhibited especially high anisotropies in the emission on the order of 10−2. 相似文献
110.
Bazzicalupi C Bencini A Bianchi A Faggi E Giorgi C Santarelli S Valtancoli B 《Journal of the American Chemical Society》2008,130(8):2440-2441