A catenane consisting of a large ring threaded through both cyclic units of a handcuff-like compound

The template effect of copper(I) allowed the preparation of a new catenane constructed around a bis-macrocyclic unit; a double ring-closing metathesis reaction afforded the central ring which is threaded through both rings of the bis-macrocycle.     

Cornelius Lanczos’s Derivation of the Usual Action Integral of Classical Electrodynamics

The usual action integral of classical electrodynamics is derived starting from Lanczos’s electrodynamics – a pure field theory in which charged particles are identified with singularities of the homogeneous Maxwell’s equations interpreted as a generalization of the Cauchy–Riemann regularity conditions from complex to biquaternion functions of four complex variables. It is shown that contrary to the usual theory based on the inhomogeneous Maxwell’s equations, in which charged particles are identified with the sources, there is no divergence in the self-interaction so that the mass is finite, and that the only approximations made in the derivation are the usual conditions required for the internal consistency of classical electrodynamics. Moreover, it is found that the radius of the boundary surface enclosing a singularity interpreted as an electron is on the same order as that of the hypothetical “bag” confining the quarks in a hadron, so that Lanczos’s electrodynamics is engaging the reconsideration of many fundamental concepts related to the nature of elementary particles.     

Optimisation of the selectivity of a pulsed flame photometric detector for unknown compound screening

Identification of traces of chemical warfare agents (CWA) is generally performed with spectral methods such as mass spectrometry (MS) or NMR, but the use of element-specific detectors is most often required to extract interesting signals from gas chromatographic (GC) data heavily masked by natural interferents. The pulsed flame phosphorus detector (P-FPD) is able to detect phosphorus, sulphur and arsenic, and thus should be very well-suited to CWA detection. However, first results using standard operating conditions recommended by the manufacturer of P-FPD led to false positive detection of phosphorus-containing compounds on the sulphur line. Therefore, an optimisation process of the selectivity of P-FPD for phosphorus versus sulphur or arsenic was undertaken, and allowed to identify gate delay and gate width as crucial parameters for the performance of P-FPD. While selectivity could be significantly improved, unexpectedly, this resulted in a concurrent important loss of sensitivity (ca. 45%) for arsenic, which suggests that this detector should be carefully optimised with respect, and prior to its purported use.     

Courants positifs extrêmaux et conjecture de Hodge

Sans résumé     

Analogues du nor-B benzomorphane. I. Synthese des méthano-3,5 tétrahydro-2,3,4,5 1H-benzazépines et dérivés

A series of new homologous B-norbenzomorphans, the 3,5-methano-2,3,4,5-tetrahydro-lH-l- and 2-benzazepines inculding 7- and 8-intro or amino derivatives have been synthesized as potential CNS drugs.     

Holographic behaviour of channelled spectra in space and time optics

A channelled spectrum being essentially a spectral distribution of energy modulated or filtered when passing through an optical system (e.g. an interferometer) it is shown that it behaves as a hologram in which longitudinal information is coded as a function of the temporal frequency. Holographic recordings are then generally considered in the temporal (or longitudinal) domain that offers a wide range of metrological applications.