Saturation behavior of SF6at high pressure and laser intensity

An experimental study of the saturable absorption of SF6at high pressure with high incident laser flux is reported. Experiments with a high-pulse-power CO2laser show 15 orders of magnitude change in transmittance of SF6(17 torr pressure) at theP(16) CO2line and apparent saturation of the residual absorption atP(20) andP(22) CO2wavelength. Comparison of these results with behavior predicted by a four-level model yields reasonable agreement over certain intensity ranges.     

Nuclear gamma-ray emission from antiproton annihilation at rest in uranium

We have observed low energy nuclear gamma-rays, which we interpret as coming from fission fragments, from antiproton annihilation at rest in a uranium target. The high gamma-ray and previously reported fission neutron temperatures, as well as large relative neutron-to-gamma ray yields, suggest a high level of excitation of the fission fragments.     

Search for new SS states in the K− induced K+K− system

Results from the first PWA of the K⁺K^? system produced by incident K^?, are presented in the mass range from the threshold to 1.70 GeV. In the P and D waves only the φ and f′ mesons are observed and their production mechanism studied. A broad S wave peaking at 1.4 GeV is observed but the lack of information about its phase makes the search for new 0⁺⁺ mesons inconclusive.     

Synthesis and spectroscopic properties of the novel cationic alkyne complexes [WI(CO)(NCMe)L2(η-RC2R)][BF4] (L = PEt3 or PMe2Ph; R = Me or Ph)

The complexes [WI₂(CO)L₂(η²-RC₂R)] (L = PEt₃ or PMe₂Ph; R = Me or Ph) react with an equimolar quantity of Ag[BF₄] in acetonitrile at room temperature to give good yields of the new purple cationic alkyne complexes [WI(CO)(NCMe)L₂(η²-RC₂R)][BF₄]. ³¹P NMR spectroscopy indicates that the phosphines are trans to each other in these compounds. ¹³C NMR spectroscopy suggests that the alkyne ligands are donating four electrons to the tungsten in these complexes.     

The impedance of sintered plate cadmium electrodes in alkaline solution

It has been shown that the a.c. impedance of a sintered plate cadmium electrode can be related to that for a planar cadmium electrode by considering the penetration of the a.c. signal down the pores of the sinter matrix. Evenly and poorly-impregnated electrodes were studied and complex impedance plane plots obtained for regions corresponding to double layer charging, active dissolution and passivation. At high frequencies when porous behaviour was observed, the results displayed a close agreement with those predicted by the simple a.c. theory developed for a porous electrode with semi-infinite pores. Discrepancies could be attributed to the presence of uncharged Cd(OH)₂ or Cd(OH)₂ precipitate formed during discharge. The effect of charge-discharge cycling was investigated and the resulting impedance spectra interpreted in terms of changes in the wetted areas of cadmium, redistribution of active material and the progressive build up of Cd(OH)₂ within the sinter pores.