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71.
Makins NC Ent R Chapman MS Hansen J Lee K Milner RG Nelson J Arnold RG Bosted PE Keppel CE Lung A Rock SE Spengos M Szalata ZM Tao LH White JL Coulter KP Geesaman DF Holt RJ Jackson HE Papavassiliou V Potterveld DH Zeidman B Arrington J Beise EJ Belz E Filippone BW Gao H Lorenzon W Mueller B McKeown RD O'Neill TG Epstein M Margaziotis DJ Napolitano J Kinney E Anthony PL van Bibber K Dietrich FS Gearhart RA Patratos GG Kuhn SE van den Brand JF Bulten H Jones CE 《Physical review letters》1994,72(13):1986-1989
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73.
Dasu S de Barbaro P Bodek A Harada H Krasny MW Lang K Riordan EM Andivahis L Arnold R Benton D Bosted P deChambrier G Lung A Rock SE Szalata ZM Walker RC Filippone BW Jourdan J Milner R McKeown R Potterveld D Para A Dietrich F Van Bibber K Button-Shafer J Debebe B Hicks RS Gearhart R Whitlow LW Alster J 《Physical review D: Particles and fields》1994,49(11):5641-5670
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Anthony PL Arnold RG Band HR Borel H Bosted PE Breton V Cates GD Chupp TE Dietrich FS Dunne J Erbacher R Fellbaum J Fonvieille H Gearhart R Holmes R Hughes EW Johnson JR Kawall D Keppel C Kuhn SE Lombard-Nelsen RM Marroncle J Maruyama T Meyer W Meziani Z Middleton H Morgenstern J Newbury NR Petratos GG Pitthan R Prepost R Roblin Y Rock SE Rokni SH Shapiro G Smith T Souder PA Spengos M Staley F Stuart LM Szalata ZM Terrien Y Thompson AK White JL Woods M Xu J Young CC Zapalac G 《Physical review D: Particles and fields》1996,54(11):6620-6650
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77.
Lung A Stuart LM Bosted PE Andivahis L Alster J Arnold RG Chang CC Dietrich FS Dodge WR Gearhart R Gomez J Griffioen KA Hicks RS Hyde-Wright CE Keppel C Kuhn SE Lichtenstadt J Miskimen RA Peterson GA Petratos GG Rock SE Rokni SH Sakumoto WK Spengos M Swartz K Szalata Z Tao LH 《Physical review letters》1993,70(6):718-721
78.
U. Groß P. Dietrich G. Engler D. Prescher J. Schulze K. Lunkwitz A. Ferse 《Journal of fluorine chemistry》1982,20(1):33-52
The present work studies the changes in polymer structure and the mechanism of the decomposition of polytetrafluoroethylene resin (PTFE) exposed to high energy radiation (electron beam). Spectroscopic and kinetic observations are used to interpret the degradation process. For the first time the decomposition of PTFE has been carried out on a preparative scale and new results obtained by analysing the degradation products. The radiation-induced degradation of PTFE is accompanied by thermal degradation under certain irradiation conditions. This is due to an increase in temperature of the polymer caused by retardation of highly accelerated electrons (heat accumulation effect).The kinetics are discussed in terms of the reactions and recombination of radicals produced by high-energy radiation both in the polymer melt and the polymer surface. These are related to the overall rate of decomposition.The primary radicals formed by decomposition of PTFE in an inert atmosphere (N2, Ar) react to produce perfluorinated alkanes and alkenes. In the presence of reactive gases the decomposition fragments originated will react rapidly; e.g. if oxygen is present in the reactive area the radicals form perflourinated peroxyl and oxyl radicals which finally stabilize themselves by CC-scission to perfluorocarbon acid fluorides and carbonyldifluorides. 相似文献
79.
In present telecommunication networks, information transfer relies on the interplay of optical and electrical signals. Data are communicated optically but processed electronically. Methods to maintain the propagating signals solely at the optical level must be developed to overcome the transmission capacities and speed limits imposed by the electronic components. We have demonstrated that molecular switches can be used to gate optical signals in response to optical signals. We have realized a simple optical network consisting of three light sources, one cell containing a solution of three fluorescent molecules, one cell containing a solution of a three-state molecular switch and a detector. The light emitted by the three fluorophores is absorbed by the three states of the molecular switch. Using this simple operating principle, we have shown that multichannel digital transmission can be implemented on an ensemble of communicating molecules relying exclusively on the interplay of optical inputs and optical outputs. 相似文献
80.
Carlo Costa Antonella Bertazzo Graziella Allegri Silvia Catinella Pietro Traldi 《Journal of mass spectrometry : JMS》1991,26(11):972-976
The electron impact-induced fragmentation processes of pyrrole-2-, -3-, -2,3-, -3,4-, -2,5- and -2,3,4-carboxylic acids were investigated with the aid of metastable ion, collisional and deuterium labelling experiments. The general behaviour of these compounds is discussed in detail, together with the reasonable structures of the more relevant fragment ions. 相似文献