Carbon atoms molecular beam production

Electronic excitation from atom-transfer reactions appears to be relatively uncommon, with most such reactions producing chemiluminescence from vibrationaHy excited ground states (188—191). Examples include reactions of oxygen atoms with carbon disulfide (190), acetylene (191), or methylene (190), all of which produce emission from vibrationaHy excited carbon monoxide. When such reactions are carried out at very low pressure (13 mPa (lO " torr)), energy transfer is diminished, as with molecular beam experiments, so that the distribution of vibrational and rotational energies in the products can be discerned (189). Laser emission at 5 p.m has been obtained from the reaction of methylene and oxygen initiated by flash photolysis of a mixture of SO2, 2 2 6 (1 )-... 

Carbon monoxide also is formed by the reaction of ground state O atoms with OCS the CO vibrational distribution closely resembles the A + BCD prior distribution,or a 9500 K Boltzmann distribution, and = O il- The reaction channel forming SO + CO has a 5 kcal mole" activation energy, and probably corresponds to the SO + CS channel of the O + CS2 reaction. The similarity of and for the two reactions supports this contention. The CO + SO products were not observed in molecular-beam experiment with Et = 5 kcal mole S which is the magnitude of the activation energy. 

More exact production methods have been developed during the last decade for clusters in beams but with the drawback that these methods only produce microscopic aunounts of clusters. These developments go back to the classical work on molecular and atomic beams by Ramsey [35] and recent overviews have been given by Scoles [80], de Heer [54] and Haberland [55]. The first modern production of metal and carbon clusters was accomplished by Furstenau and Hillenkamp [81] using the laser microprobe mass spectrometer, LAMMA,... 

Electron beam crosslinking takes place when very high energy radiation is used to initiate molecular crosslinking in high-density polyethylene. This product is extruded like normal HDPE then taken to an E-beam facility and routed under a beam or ray in the accelerator where it is dosed with a specific amount of radiation to release the hydrogen atoms and cause polymer chains to bond or link to the open carbon sites. 

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