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41.
A two-photon laser-induced fluorescence study on the transport of ground-state atomic hydrogen in a supersonic plasma jet, generated from an Ar-H (2) mixture, reveals an unexpected shock pattern. Whereas both the axial-velocity profile and the temperature profile of hydrogen atoms along the jet centerline can be interpreted in terms of a supersonic expansion of an Ar-H gas mixture, the H-atom density profiles do not satisfy the well established Rankine-Hugoniot relation leading to a nonconservation of the forward flux. The experimental results show that H atoms escape from the supersonic expansion by a diffusion process due to strong density gradients between the core of the jet and its vicinity. 相似文献
42.
[Structure: see text] Reaction of 4-hydroxyisophthalaldehyde with excess phenyl magnesium bromide gave a dicarbinol and this condensed with pyrrole and aromatic aldehydes in the presence of BF3.Et2O to afford, following oxidation with DDQ, novel tetraarylcarbaporphyrinoids in 10-24% yield. Further reaction with silver(I) acetate or gold(III) acetate gave stable organometallic derivatives that retained the aromatic characteristics of the parent macrocycle. 相似文献