On elimination of quantifiers in some non‐classical mathematical theories

Elimination of quantifiers is shown to fail dramatically for a group of well‐known mathematical theories (classically enjoying the property) against a wide range of relevant logical backgrounds. Furthermore, it is suggested that only by moving to more extensional underlying logics can we get the property back.     

Convergence analysis of the FEM approximation of the first order projection method for incompressible flows with and without the inf-sup condition

In this paper we obtain convergence results for the fully discrete projection method for the numerical approximation of the incompressible Navier–Stokes equations using a finite element approximation for the space discretization. We consider two situations. In the first one, the analysis relies on the satisfaction of the inf-sup condition for the velocity-pressure finite element spaces. After that, we study a fully discrete fractional step method using a Poisson equation for the pressure. In this case the velocity-pressure interpolations do not need to accomplish the inf-sup condition and in fact we consider the case in which equal velocity-pressure interpolation is used. Optimal convergence results in time and space have been obtained in both cases.     

Sulfate complexation of trivalent lanthanides probed by nanoelectrospray mass spectrometry and time-resolved laser-induced luminescence

Sulfate complexation of lanthanides is of great interest for predicting speciation of radionuclides in natural environments. The formation of LaSO4+(aq) in HNO3/H2SO4 aqueous solutions of low ionic strength (I) was studied by nanoelectrospray ionization mass spectrometry (nanoESI-MS). Several gaseous species containing LaSO4+ were detected. The formation constant of LaSO4+(aq) was determined and extrapolated to I = 0 (log = 3.5 +/- 0.3) by using a simple specific ion interaction theory (SIT) formula. This value supports the potential of nanoESI-MS for the study of kinetically labile species. The species La(SO4)(2-) was also detected. In addition, time-resolved laser-induced luminescence (TRLIL) was used to study Eu(III) speciation under ionic conditions of 0.02-0.05 M H+ (H2SO4/HClO4) and 0.4-2.0 M Na+ (Na2SO4/NaClO4). The data were interpreted with the species EuSO4+ (log = 3.7(8) +/- 0.1) and Eu(SO4)(2-) (log = 1.5 +/- 0.2). For extrapolating to I = 0, all of the major ions were taken into account through several SIT ion-pair parameters, epsilon. Most of the epsilon values were estimated by analogy to known parameters for similar ion-pair interactions using linear correlations, while epsilon(Eu)3+,SO4(2-) = 0.8(6) +/- 0.5 was fitted to the experimental data because, to date, SIT coefficients between multicharged species are not reported. The formation constants obtained here confirm some of those previously measured for Ln(III) and An(III) by various experimental techniques, and conversely do not give credit to the idea that in equilibrium conditions TRLIL and other spectroscopic techniques would provide stability constants of only inner-sphere complexes. The fluorescence lifetimes measured for EuSO4+ and Eu(SO4)(2-) were consistent with the replacement of one H2O molecule in the first coordination sphere of Eu3+ for each added SO4(2-) ligand, suggesting a monodentate SO4(2-) coordination.     

An Artificial Lithium Protective Layer that Enables the Use of Acetonitrile‐Based Electrolytes in Lithium Metal Batteries

The resurgence of the lithium metal battery requires innovations in technology, including the use of non‐conventional liquid electrolytes. The inherent electrochemical potential of lithium metal (?3.04 V vs. SHE) inevitably limits its use in many solvents, such as acetonitrile, which could provide electrolytes with increased conductivity. The aim of this work is to produce an artificial passivation layer at the lithium metal/electrolyte interface that is electrochemically stable in acetonitrile‐based electrolytes. To produce such a stable interface, the lithium metal was immersed in fluoroethylene carbonate (FEC) to generate a passivation layer via the spontaneous decomposition of the solvent. With this passivation layer, the chemical stability of lithium metal is shown for the first time in 1 m LiPF₆ in acetonitrile.     

Identification of physical parameters in pressing of rapeseeds from the oil flux measurements

In this paper, we are interested in the study of an inverse problem that occurs during the pressing of rapeseeds, where some physical parameters influence on rapeseed oil extraction yield. Our objective is to identify the consolidation coefficient of the press cake, the inverse characteristic time of consolidation in press cake, and inside the rapeseed in order to increase the rapeseed oil extraction yield. Three questions will be addressed: the identifiability, the identification, and the stability of the inverse problem. Finally, we provide numerical results to confirm the theoretical results.     

Synthesis,Crystal Structures and Thermal Analysis of Two New Silver(I)–Dithioether Lamellar Coordination Polymers

Abstract  Two new silver(I)–dithioether coordination polymers based on the self-assembly of the dithioether ligands L ^{n −R} = CH₃–S(CH₂) _n S–CH₃ (n = 1, 3) and AgX silver salts, where X = ClO₄ ⁻ (1) and PF₆ ⁻ (2), have been synthesized and characterized by single crystal X-ray diffraction and TGA. The crystallographic data of those complexes are: (1) Monoclinic P2₁/c; a = 16.5861(3) ?; b = 10.1048(2) ?; c = 15.7843(3) ?; β = 112.570(1)°; V = 2442.83(8) ?³; Z = 4. (2) Monoclinic P2₁/n; a = 8.6500(2) ?; b = 9.4053(2) ?; c = 24.0357(6) ?; β = 92.750(2)°; V = 1953.19(8) ?³; Z = 4. In both complexes, the dithioether building blocks propagated the silver(I) centers to build cationic lamellar coordination polymers, while ClO₄ ⁻ and PF₆ ⁻, which were sandwiched between silver-ligand sheets, counterbalance only the charge of the networks. The thermogravimetric investigation reveals that those complexes decompose in a single step respectively to metallic silver and silver salt. Index Abstract  Two new silver(I)–dithioether coordination polymers, obtained from the self-assembly of dithioether ligands and AgX salts with noncoordinating counteranions (X = ClO₄ ⁻ and PF₆ ⁻), were characterized by X-ray crystallography and thermogravimetric analysis (TGA).