Search results for "LIMIT"
showing 10 items of 2826 documents
An attempt to realise the constrained search approach in the density functional theory
2001
Abstract The problem of reconstruction of wave functions from a given electron density is considered. A reformulation of the problem is proposed which is based on the Fourier transform. Arising mathematical problems are studied, namely, the properties of reduced spatial densities and their Fourier images are obtained, which follow from known properties of the wave functions. The proposed approach may provide a practical implementation of the Constrained Search Approach to the DFT.
Λb and Λc baryon decays at finite values of heavy quark masses
2000
Semileptonic decays of Lambda_b and Lambda_c baryons are studied within the Relativistic Three-Quark Model using finite heavy quark mass values. Employing the same parameters as have been used previously for the description of exclusive decays of heavy baryons in the heavy quark limit we calculate the six form factors of the process and the corresponding decay rates. Our calculation shows that the ``finite mass'' corrections are important in heavy-to-light transitions and are not negligible in heavy-to-heavy transitions.
From CCSD(T)/aug-cc-pVTZ-J to CCSD(T) complete basis set limit isotropic nuclear magnetic shieldings via affordable DFT/CBS calculations
2011
It is shown that a linear correlation exists between nuclear shielding constants for nine small inorganic and organic molecules (N2, CO, CO2, NH3, CH4, C2H2, C2H4, C2H6 and C6H6) calculated with 47 methods (42 DFT methods, RHF, MP2, SOPPA, SOPPA(CCSD), CCSD(T)) and the aug-cc-pVTZ-J basis set and corresponding complete basis set results, estimated from calculations with the family of polarization-consistent pcS-n basis sets. This implies that the remaining basis set error of the aug-cc-pVTZ-J basis set is very similar in DFT and CCSD(T) calculations. As the aug-cc-pVTZ-J basis set is significantly smaller, CCSD(T)/aug-cc-pVTZ-J calculations allow in combination with affordable DFT/pcS-n com…
Estimation of isotropic nuclear magnetic shieldings in the CCSD(T) and MP2 complete basis set limit using affordable correlation calculations
2013
A linear correlation between isotropic nuclear magnetic shielding constants for seven model molecules (CH2O, H2O, HF, F2, HCN, SiH4 and H2S) calculated with 37 methods (34 density functionals, RHF, MP2 and CCSD(T)), with affordable pcS-2 basis set and corresponding complete basis set results, estimated from calculations with the family of polarization-consistent pcS-n basis sets is reported. This dependence was also supported by inspection of profiles of deviation between CBS estimated nuclear shieldings and shieldings obtained with the significantly smaller basis sets pcS-2 and aug-cc-pVTZ-J for the selected set of 37 calculation methods. It was possible to formulate a practical approach o…
Fuel cell modelling for power supply systems design
2008
Today academic and industrial research is addressed on fuel cell based power supply to replace current lithium-ion and similar rechargeable battery systems. For system simulation, fuel cell models are developed. Even if power electronics designers demand for a blackbox model to limit the knowledge of physical and chemical parameters, high performance in terms of model accuracy and portability is absolutely necessary. A steady state and dynamic fuel cell model oriented to power supply systems design is proposed and, as an example, the implementation on PSIM software is presented. Simulation and experimental results are compared and the model portability is discussed. ©2008 IEEE.
Experimental observations of upstream overdeepening
2005
The issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence, depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels, while narrower stream…
I beni confiscati alla mafia: verso la riconquista della legalità
2003
La Legge 7 marzo 1996, n.109, Disposizioni in materia di gestione e destinazione di beni sequestrati o confiscati, può essere considerata, uno strumento fondamentale per la lotta alla criminalità organizzata. Partendo dal presupposto che la lotta alla mafia debba passare anche attraverso l'attacco al capitale economico dell'organizzazione, in quanto base del potere mafioso, la legge n. 109/96 si inserisce in una strategia dal profondo significato simbolico, in quanto prevede che la destinazione d'uso dei beni confiscati debba essere sociale e istituzionale. In tal modo si cerca di proporre e affermare sul territorio il modelli della legalità attraverso il riutilizzo di beni che rappresentav…
Chromatographic separation of chlorthalidone enantiomers using β-cyclodextrins as chiral additives
2000
Different beta-cyclodextrins have been tested as chiral additives in the mobile phase for the chromatographic analysis of chlorthalidone enantiomers in a C18 LiChrospher (125 x 4 mm I.D.) column. The effect on enantioresolution of different parameters was studied: composition of the mobile phase (percentage of organic solvent, type of buffer and pH), mobile phase flow-rate, and type and concentration of beta-cyclodextrin. A 25:75 mixture of methanol and 0.1 M phosphate buffer, pH 4, containing 2% triethylamine (v/v), and 12.5 mM beta-cyclodextrin, at a flow-rate of 0.8 ml/min, was found to be the best option for the resolution of chlorthalidone enantiomers. Under such conditions, linear cal…
A Derivation of the Vlasov-Stokes System for Aerosol Flows from the Kinetic Theory of Binary Gas Mixtures
2016
In this short paper, we formally derive the thin spray equation for a steady Stokes gas, i.e. the equation consists in a coupling between a kinetic (Vlasov type) equation for the dispersed phase and a (steady) Stokes equation for the gas. Our starting point is a system of Boltzmann equations for a binary gas mixture. The derivation follows the procedure already outlined in [Bernard-Desvillettes-Golse-Ricci, arXiv:1608.00422 [math.AP]] where the evolution of the gas is governed by the Navier-Stokes equation.
A class-selective immunoassay for simultaneous analysis of anilinopyrimidine fungicides using a rationally designed hapten
2017
he development of multianalyte immunoassays constitutes a main research issue in the field of bioanalytical techniques. In the present study, class-specific antibodies against the three members of the anilinopyrimidine family of fungicides (pyrimethanil, cyprodinil and mepanipyrim) were raised by using a bioconjugate of a rationally designed hapten [5-(6-methyl-2-(phenylamino)pyrimidin-4-yl)pentanoic acid]. Highly sensitive immunoassays were developed for the generic determination of these compounds, using the competitive enzyme-linked immunosorbent assay (ELISA). Particularly, a direct antibody-coated competitive ELISA afforded identical sensitivity for the three anilinopyrimidines, with I…