Unsharp quantum logics

The event-structure of a state-event system, containing unsharp elements, can be described either as aregular involutive bounded poset, or alternatively as anunsharp orthoalgebra (called alsodifference poset oreffect algebra). Such structures give rise to different forms ofunsharp quantum logics.     

Hydro-de-halogenation and consecutive deprotection of chlorinated N-amido-pyrrolidin-2-ones with Raney-Ni: an effective approach to gabapentin

The benzoylamino group was identified as a useful radical cyclization auxiliary that can be smoothly removed on hydro-de-halogenation of chlorinated N-substituted-pyrrolidin-2-ones with Raney-Ni. This methodology was successfully implemented in a new and appealing route to the anti-epileptic drug gabapentin.     

Inductively coupled plasma—atomic emission spectrometry (ICP-AES): an analytical technique for the chemical characterization of perovskite ceramic semiconductors

The possibilities of inductively coupled plasma-atomic emission spectrometry (ICP-AES) for the chemical characterization (dopants, impurities, and macroconstituents) of perovskite ceramic semiconductors (PTC thermistors, varistors, manganites, cobaltites) are shown. The dissolution of the samples is achieved by five methods: (a) decomposition with HCl in a Teflon-lined pressure vessel, (b) decomposition with HF + H₂SO₄ in a Teflon-lined pressure vessel, (c) decomposition with (NH₄)₂SO₄ + H₂SO₄ in a platinum dish, (d) fusion with Na₂CO₃ + Na₂B₄O₇ in a platinum crucible, (e) fusion with Li₂B₄O₇ in a graphite crucible. The spectral interferences and the inter-element effects are studied and corrected. The detection limits are comprised, approximately, between 0.00001% and 0.1%. High sensitivity and good precision are attained.     

Radioresistance studies in Methylobacterium spp.

Methylobacterium extorquen was isolated and was found as one of the most resistant microorganisms in the original bioburden of ophthalmic cotton dressings to be submitted to γ radiation sterilization. Radiation survival curves were simultaneously performed in phosphate buffer and in test-pieces on two isolates, one obtained before irradiation (wild strain) and the other after irradiation at 20 kGy (rad strain), as well as on three type strains of Methylobacterium spp. (M. extorquens^T, M. radiotolerans^T and M. fujisawaense^T). The radiation resistance was compared using D_values. To analyze the effect of non linearity on radioresistance other measures were applied, such as intercept point, fraction of surviving cells at a selected dose and area. The ranking of strains with these approaches showed to be different, pointing out the need of an integrated measure of radioresistance. Therefore, an index of relative survival (IRS) is proposed.     

Regioselective reductive demethoxylation of 3,4,5-trimethoxystilbenes

Selective removal of the 4-methoxy group of 3,4,5-trimethoxystilbenes was performed under electron transfer conditions from Na metal in THF. Careful control of reaction conditions and quenching procedure allowed the synthesis of either (E)-3,5-dimethoxystilbenes or 3,5-dimethoxybibenzyls.     

Derivations on Lie ideals in semiprime rings

We prove that ifR is a semiprime 2-torsion free ring with a derivationd andU a Lie ideal ofR such thatd ² (U)=0, thend(U)?Z(R), the center ofR.     

Mercury(II) oxide/tetrafluoroboric acid. An unusual behavior in the oxidation of alkenes. Synthesis of trans-cinnamylethers

The synthesis of $\text{trans}$-cinnamylethers by oxidation of allylbenzene is described. The reaction cannot be explained by formation of an allylic mercurial. A new type of mechanism in the oxidation of alkenes by mercury(II) salts is proposed.