Regularity of a class of subLaplacians on the 3-dimensional torus

In this paper we present a necessary and sufficient condition for a family of sums of squares operators to be globally hypoelliptic on a torus. This condition says that either a Diophantine condition is satisfied or there exists a point of finite type. Also, we describe the analytic and Gevrey versions of this result. The proof is based on L²-estimates and microlocal analysis.     

First observation of 55, 56Zn

In an experiment at the SISSI/LISE3 facility of GANIL, the most proton-rich zinc isotopes ^55,56Zn have been observed for the first time. The experiment was performed using a high-intensity ⁵⁸Ni beam at 74.5 MeV/nucleon impinging on a nickel target. The identification of ^55,56Zn opens the way to ⁵⁴Zn, a good candidate for two-proton radioactivity according to theoretical predictions. Received: 31 October 2000 / Accepted: 9 November 2000     

Concepts for structurally robust materials that combine low thermal expansion with high stiffness

A family of robust stretch-dominated bimaterial lattices is introduced which combines low (or zero) thermal expansion with high stiffness, structural robustness over wide temperature ranges and manufacturing facility. This combination of properties is unavailable through any other material solution. The concept uses two constituents configured as adjoining sub-lattices. It accommodates the thermal expansion through rotation of the members of one sub-lattice. Moreover, the lattice exhibits large stiffness to weight because it is fully triangulated and does not rely on rotational resistance at the joints for structural rigidity. A wide range of constituents can be used to build the new lattices enabling many desirable properties to be incorporated, especially high strength and toughness. Examples of both planar and volumetric lattices are presented, and their thermo-mechanical properties derived. The results are verified by conducting experiments and finite element simulations on a lattice fabricated using aluminium and titanium alloy constituents.     

Association of two 3D QSAR analyses. application to the study of partial agonist serotonin-3 ligands.

CATALYST and COMFA, two software packages for 3D QSAR studies, were associated to correlate the three-dimensional structures of 75 serotonin 5-HT3 ligands to their biological affinities. The conformational analysis and the influence of chemical function-based alignments (the basis of this association) on final results are discussed in this publication. These two analyses allow for precisely quantitating the weights of significant chemical groups or functions on the biological affinities.     

Exciton transport by surface acoustic waves

Long-range acoustic transport of excitons in GaAs quantum wells (QWs) is demonstrated. The mobile strain field of a surface acoustic wave creates a dynamic lateral type I modulation of the conduction and valence bands in a double-quantum-well (DQW) structure. This mobile potential modulation transports long-living indirect excitons in the DQW over several hundreds of μm.     

Photoinduced,Direct C(sp2)−H Bond Azo Coupling of Imidazoheteroarenes and Imidazoanilines with Aryl Diazonium Salts Catalyzed by Eosin Y

Herein, a greener approach to the eosin Y-Na₂ catalyzed, C(sp²)−H bond azo coupling of imidazoheteroarene with aryl diazonium salts is described, under acid free conditions. This direct photoredox process resulted in the corresponding azo products in good to excellent yields. Besides, this new approach could also be applicable to anilines, which is a poorly reactive substrate by other methods. The main features of this reaction are that it provides high yields and is gram-scalable and applicable to biologically relevant imidazoheteroarenes and -anilines.     

Highly sensitive photoelectrochemical immunosensor based on anatase/rutile TiO2 and Bi2S3 for the zero-biased detection of PSA

Journal of Solid State Electrochemistry - A novel label-free photoelectrochemical immunosensor was developed for the determination of prostate-specific antigen (PSA) based on fluorine-doped tin...     

Electronic and structural properties of black phosphorene doped with Si,B and N

The electronic and structural properties of substitutional and doped phosphorene with B, N and Si were studied using first principles calculations based on density functional theory. Moreover, electronic and structural properties of functionalized phosphorene slowly increasing the concentration of doping was investigated. Phosphorene strongly binds with doped functionalization; B doped phosphorene is the most stable configuration studied. Si doped phosphorene maintains the semiconductor characteristic. B and N doped phosphorene present n-type and p-type semiconductors, respectively. Doped phosphorene with odd number of Si is a semiconductor material, doped phosphorene with an odd number of B has n-type semiconductor characteristic, and doped phosphorene with odd number of N atoms has a p-type semiconductor behaviour. Doped phosphorene with even number of Si has a metallic characteristic, while B and N doped phosphorene with even number present a semiconductor behaviour. This work reveals that phosphorene electronic properties could be changed by introducing the dopants on the system, and the properties are affected by the increasing number of dopants on phosphorene sheet.