Solar thermochemical reactions Ⅱ: Synthesis of 2-aminothiophenes via Gewald reaction induced by solar thermal energy

Green conditions have been developed for the synthesis of substituted 2-aminothiopbenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal energy.     

Time averaging for the strongly confined nonlinear Schrödinger equation, using almost-periodicity

We study the limiting behavior of a nonlinear Schrödinger equation describing a 3-dimensional gas that is strongly confined along the vertical, z direction. The confinement induces fast oscillations in time, that need to be averaged out. Since the Hamiltonian in the z direction is merely assumed confining, without any further specification, the associated spectrum is discrete but arbitrary, and the fast oscillations induced by the nonlinear equation entail countably many frequencies that are arbitrarily distributed. For that reason, averaging cannot rely on small denominator estimates or like.To overcome these difficulties, we prove that the fast oscillations are almost-periodic in time, with values in a Sobolev-like space that we completely identify. We then exploit the existence of long-time averages for almost-periodic functions to perform the necessary averaging procedure in our nonlinear problem.     

A mathematical model for the transient evolution of a resonant tunneling diodeModélisation d'une diode à effet tunnel résonant en régime transitoire

A mathematical model of quantum transient transport is derived and analyzed. The model describes the evolution of electrons injected into the “device” by reservoirs having a stationary statistics. The electrostatic potential in the device is modified by electron presence through electrostatic interaction. The wave functions are computed in the device region and satisfy non homogeneous open boundary conditions at the device edges. A priori estimates are deduced from the “dissipative properies” of the boundary conditions and from the repulsive character of the electrostatic interaction. To cite this article: N. Ben Abdallah, O. Pinaud, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 283–288.     

Block based embedding of encrypted watermarks using singular value decomposition

Watermarking is a solution to the problem of copyright protection of multimedia documents over the Internet. This paper presents a block based watermarking scheme using the singular value decomposition (SVD) algorithm to embed encrypted watermarks into digital images. The paper compares between the traditional method of Liu and the proposed method for embedding encrypted watermarks. Also, a permutation based encryption algorithm and a diffusion based encryption algorithm are compared as the watermark encryption algorithms. Experimental results show that the proposed method is superior to the traditional method of Liu for embedding encrypted watermarks and extracting them efficiently under attacks. Results also show that it is preferred to use permutation based encryption algorithms than diffusion based encryption algorithms for watermark encryption due to their lower sensitivity to attacks.     

Search for dilepton resonances in pp collisions at √s=7 TeV with the ATLAS detector

This Letter reports on a search for narrow high-mass resonances decaying into dilepton final states. The data were recorded by the ATLAS experiment in pp collisions at √s=7 TeV at the Large Hadron Collider and correspond to a total integrated luminosity of 1.08 (1.21) fb(-1) in the e(+)e(-) (μ(+)μ(-)) channel. No statistically significant excess above the standard model expectation is observed and upper limits are set at the 95% C.L. on the cross section times branching fraction of Z' resonances and Randall-Sundrum gravitons decaying into dileptons as a function of the resonance mass. A lower mass limit of 1.83 TeV on the sequential standard model Z' boson is set. A Randall-Sundrum graviton with coupling k/M(Pl)=0.1 is excluded at 95% C.L. for masses below 1.63 TeV.     

FL-MAC-RDP: Federated Learning over Multiple Access Channels with Rényi Differential Privacy

International Journal of Theoretical Physics - Federated Learning (FL) is a promising paradigm, where the local users collaboratively learn models by repeatedly sharing information while the data...     

Stereocontrolled Syntheses of Tetralone‐ and Naphthyl‐Type Lignans by a One‐Pot Oxidative [3,3] Rearrangement/Friedel–Crafts Arylation

The development of a stereoselective one‐pot oxidative [3,3] sigmatropic rearrangement/Friedel–Crafts arylation that provides enantioenriched benzhydryl compounds is reported. The utility of this new transformation is demonstrated by the concise synthesis of several tetralone‐ and naphthyl‐type lignan natural products, many of which display anti‐malarial activity.     

Selective spectrophotometric determination of p-aminophenol and acetaminophen

A specific spectrophotometric method was developed for the determination of p-aminophenol and acetaminophen. The method is based on the reaction of p-aminophenol at ambient temperature with sodium sulphide in presence of an oxidant to produce a methylene blue-like dye. Different oxidizing agents were tried, e.g. Ce(IV) and Fe(III). The colour developed within 10 min and remained stable for at least 3 h. The method was applied successfully to the determination of p-aminophenol in the presence of acetaminophen without prior separation. The method was also applied to the analysis of various commercially available acetaminophen dosage forms and excellent recoveries were obtained comparable to those obtained by official procedures. The reaction product was isolated and a possible reaction mechanism was suggested.     

Density functional theory study of pyrrole adsorption on Mo(110)

The objective of the present study is to identify possible adsorption configurations of pyrrole on Mo(110) using density functional theory (DFT) calculations. Several adsorption configurations were studied including pyrrole and pyrrolyl adsorption as parallel, perpendicular, and tilted adsorption modes relative to the Mo(110) surface plane. Based on the DFT calculations, pyrrole is suggested to adsorb in a parallel mode with respect to the Mo(110) surface through its pi-orbital as mu3,eta(5)-Pyr-0 degrees with an adsorption energy of -28.7 to -31.5 kcal mol(-1). The possibility of a coexisting mode where pyrrole adsorbs on the surface with a slightly tilted molecular plane as mu3,eta(4)(N,C2,C3,C4)-Pyr-5 degrees is also likely to occur, particularly at higher pyrrole coverages. The slightly tilted configuration is suggested to arise from the lateral interactions of adsorbed pyrrole on Mo(110), and not the result of a phase transformation on the surface since this requires a relatively high activation energy as indicated by additional linear synchronous transit (LST)/quadratic synchronous transit (QST) calculations. Both adsorption geometries bond to three surface Mo atoms, and Mo(110) did not promote hydrogen abstraction. Pyrrolyl adsorption on Mo(110) is energetically possible, but unlikely to occur because gas-phase hydrogen has not been previously experimentally observed as a pyrrole decomposition product on Mo(110).