Interaction potentials and energy transfer cross sections for collisions of metastable helium and neon I: He(23 S)+Ne

Differential cross sections have been measured for He(2³ S)+Ne at kinetic energies between 28 and 370 meV. For energies above 90meV the elastic cross sections show Stückelberg oscillations from curve crossings, which lead to the energy exchange process: He(2³ S)+Ne→He(1¹ S)+Ne(2p ⁵ 4s,3d,4p). Differential cross sections for this inelastic process could be measured above 200 meV. A fit to the data gives the potentials for He(2³ S)+Ne and, less accurately, for He+Ne^*. These results offer a simple explanation, why the exothermic pumping process of the infrared lines of the HeNe laser has a threshold of about 80 meV and a small cross section.     

Experimental antiulcer drugs. 3. Some unusual transformations of the cyclopenta[c] pyrroles

The cyclopenta[c]pyrrole-4-carbonitrile ( 3 ) is transformed by hyrlroxylamine in hot alcohol to 4,5,6,6a-tetrahydro-l-imino-3,5,5,6a-tetramethyl-4-cyclopenta[c]pyrrole methyl ketone oxime ( 5 ) in contrast to the cyclopentapyrrole 10 which afforded 1,2-diacetyl-3,3,5,5-tetramethyl-cyclopentene dioxime ( 11 ). The cyclopenta[c]pyrrole-4-carboxamide 1 (R = C₆H₅) yielded the isomeric 2a,3,4,4a,5,6,6a,6b-octahydro-2a,4,4,6a-tetramethyl-5-(phenylimino)pentaleno[1,6-bc]-pyrrol-2-(1H)one ( 12 ) in hot dilute hydrochloric acid or hot 99% phosphoric acid. The amide 1 (R = C₆H₅) was transformed in the solid state by oxygen over a period of several months to a mixture of the isomeric anils, 13 and 14 of 1,7-diacetyl-7-hydroxy-4,6,6-trimethyl-2-azabicyclo-[2.2.l.]heptan-3-one( 16 ).     

Übertragung von metastabilem He auf Ne - eine Molekularstrahluntersuchung des Pumpvorganges des HeNe-Lasers

Ohne Zusammenfassung