Search for scalar and pseudoscalar bosons emitted in nuclear decays via their interactions

A search for light penetrating scalar and pseudoscalar bosons has been performed at the Jülich nuclear-reactor FRJ-1 (Merlin). In nuclear deexcitation processes pseudoscalar particles should be emitted in magnetic transitions and scalar particles in electric transitions. The experiment relies on the detection of the interaction products from the conversion of bosons in the field of an electron or a nucleus with a rotatable multi-scintillator system. The geometrical arrangement of the scintillators allows to distinguish between scalar and pseudoscalar particles via the different angular distributions of the final state photons. We obtain as upper limits for the product of production ratio and interaction cross section<i>W</i> for pseudoscalar particles W}<6.9></6.9><sup>–40</sup> cm<sup>2</sup>, and for scalar particles W}<1.3></1.3><sup>–39</sup> cm<sup>2</sup> with 90% confidence.We gratefully acknowledge the support of this experiment by the KFA Jülich and we are very grateful for most valuable discussions with H. Bechteler, H.R. Koch, O.W.B. Schult, H. Seyfarth and A. Zehnder. We would like to express our thanks to the personnel of the reactor Merlin. We also wish to acknowledge the excellent work of the technical staff of our institute in particular to E. Hermens and R. Pahlke. Thanks to H. Geller and C. Latsch who assisted with the runs.     

Ab initio studies of the protonation of CO,N2 and NO+: Calculation of the minimum energy reaction paths

<i>Ab initio</i> molecular orbital calculations employing a 4-31G basis set have been used to study the minimum energy paths for the formation of HCO<sup>+</sup>, COH<sup>+</sup>, and HCOH<sup>2+</sup> from CO by protonation. The protonation of N<sub>2</sub> to give NNH<sup>+</sup> and HNNH<sup>2+</sup> and of NO<sup>+</sup> to form HNO<sup>2+</sup> and NOH<sup>2+</sup> have also been investigated. All species formed have linear equilibrium geometries and the minimum energy path for approach of the proton is along the line-of-centers of the heavy atoms. Energy barriers to the formation of the various species are given, where appropriate, and changes in geometry, ordering of molecular orbitals and orbital occupancy are discussed.     

The solubility of bosentan in aqueous-2-propanol mixtures at several temperatures,measurement and data correlation

<b>ABSTRACT</b></p>The solubilities of bosentan (BST) in binary aqueous mixtures of 2-propanol at temperatures ranging from 293.15 to 313.15 K were determined using a shake-flask method. The produced data were modelled with the Jouyban-Acree-van’t Hoff model and difference between the predicted data and experimental ones were illustrated by percent average relative deviations (%ARD). Moreover, the thermodynamic functions of dissolution for BST in the aqueous 2-propanol solutions were computed which suggest that the dissolution process is endothermic and not spontaneous.