Accurate Complex Scaling of Three Dimensional Numerical Potentials

The complex scaling method, which consists in continuing spatial coordinates into the complex plane, is a well-established method that allows to compute resonant eigenfunctions of the time-independent Schroedinger operator. Whenever it is desirable to apply the complex scaling to investigate resonances in physical systems defined on numerical discrete grids, the most direct approach relies on the application of a similarity transformation to the original, unscaled Hamiltonian. We show that such an approach can be conveniently implemented in the Daubechies wavelet basis set, featuring a very promising level of generality, high accuracy, and no need for artificial convergence parameters. Complex scaling of three dimensional numerical potentials can be efficiently and accurately performed. By carrying out an illustrative resonant state computation in the case of a one-dimensional model potential, we then show that our wavelet-based approach may disclose new exciting opportunities in the field of computational non-Hermitian quantum mechanics.Comment: 11 pages, 8 figure

Asymptotic behaviour of the Rayleigh--Taylor instability

We investigate long time numerical simulations of the inviscid Rayleigh-Taylor instability at Atwood number one using a boundary integral method. We are able to attain the asymptotic behavior for the spikes predicted by Clavin & Williams\cite{clavin} for which we give a simplified demonstration. In particular we observe that the spike's curvature evolves like $t^3$ while the overshoot in acceleration shows a good agreement with the suggested $1/t^5$ law. Moreover, we obtain consistent results for the prefactor coefficients of the asymptotic laws. Eventually we exhibit the self-similar behavior of the interface profile near the spike.Comment: 4 pages, 6 figure

Self-similar impulsive capillary waves on a ligament

We study the short-time dynamics of a liquid ligament, held between two solid cylinders, when one is impulsively accelerated along its axis. A set of one-dimensional equations in the slender-slope approximation is used to describe the dynamics, including surface tension and viscous effects. An exact self-similar solution to the linearized equations is successfully compared to experiments made with millimetric ligaments. Another non-linear self-similar solution of the full set of equations is found numerically. Both the linear and non-linear solutions show that the axial depth at which the liquid is affected by the motion of the cylinder scales like $\sqrt{t}$. The non-linear solution presents the peculiar feature that there exists a maximum driving velocity $U^\star$ above which the solution disappears, a phenomenon probably related to the de-pinning of the contact line observed in experiments for large pulling velocities

A decade of DNA-hybrid catalysis: from innovation to comprehension

crosscheck: This document is CrossCheck deposited identifier: Michael Smietana (ORCID) identifier: Stellios Arseniyadis (ORCID) identifier: Stellios Arseniyadis (ResearcherID) copyright_licence: The Royal Society of Chemistry has an exclusive publication licence for this journal history: Received 22 January 2017; Accepted 23 April 2017; Accepted Manuscript published 25 April 2017; Advance Article published 9 May 2017We would like to thank the Agence Nationale de la Recherche for funding – the NCiS project (ANR-2010-JCJC-715-1) and the D-CYSIV project (ANR-2015-CE29-0021-01

Derived crop coefficients for winter wheat using different reference evpotranspiration estimates methods

This paper reports the results of using three empirical methods (Makkink, Priestley-Taylor and Hargreaves) for estimating the reference evapotranspiration (ET0) in the semi-arid region of Tensift Al Haouz, Marrakech (center of Morocco). The Penman-Monteith equation, standardized by the Food and Agriculture Organization (FAO-PM), is used to evaluate the three empirical methods. The obtained ET0 data were used to estimate crop water requirement (ET) of winter wheat using the crop coefficient (K-c) approach and results were compared with ET measured by the Eddy Covariance technique. The result showed that using the original empirical coefficients a, alpha and C-m in Hargreaves, Priestley-Taylor and Makkink equations, respectively, the Hargreaves method agreed fairly well with FAO-PM method at the test site. Conversely, the Priestley-Taylor and Makkink methods underestimate the ET by about 20 and 18 %. After adjustment of the original values of two parameters alpha and C-m coefficients in Priestley-Taylor and Makkink equations, the underestimation of ET was reduced to 9% and 4% for the Priestley Taylor and Makkink methods, respectively, which led to an improvement of 55% and 76% of the obtained values compared with the original values

Calibration and validation of the STICS crop model for managing wheat irrigation in the semi-arid Marrakech/Al Haouz Plain

In the first part of this work, the shoot growth module and grain yield of the STICS crop model were calibrated and validated by using field data which was collected from irrigated winter wheat fields in the Haouz plain near Marrakech. The calibration was performed on the thermal units between the four phenological stages that control the dynamics of leaf area index and the thermal unit between emergence and the beginning of grain filling. The plant phenology was calibrated for three fields monitored during the 2002/03 season. Evaluation of the grain yields and the temporal evolution of leaf area index were done for six validation fields during 2003/04. The results showed the significant accuracy of the model in simulating these variables, and also indicated that the plants mainly suffered from lack of nitrogen. The results in the second part show the potential of crop modeling to schedule irrigation water, on the assumption that the plants were growing under optimal conditions of fertilization. In this case, the model was used to manage the time of irrigation according to a threshold for water deficit. Various simulations displayed logical trends in the relationship between the grain yield and both the amount and timing of irrigation water. These results were finally compared with those obtained from real irrigation practices. For the particular climate of 2003/04, the comparison showed that 70 mm and 40 mm of water could be saved in case of early and late sowing, respectively

DNA-cellulose: an economical, fully recyclable and highly effective chiral biomaterial for asymmetric catalysis

similarity_check: This document is Similarity Check deposited related_data: Supplementary Information copyright_licence: The Royal Society of Chemistry has an exclusive publication licence for this journal peer_review_method: Single-blind history: Received 20 December 2014; Accepted 11 January 2015; Accepted Manuscript published 14 January 2015; Advance Article published 23 January 2015; Version of Record published 24 March 2015This research was supported by the Ministe`re de l’Enseignement Supe´rieur et de la Recherche and the Agence Nationale de la Recherche (NCiS; ANR-2010-JCJC-715-1)