OPTICAL TRANSMITTANCE OF FUSED SILICA AT ELEVATED TEMPERATURES DURING HIGH ENERGY ELECTRON BOMBARDMENT

The medium temperature pyrolysis process using a fixed-bed reactor at atmospheric pressure was utilised to recover carbon black from motorcycle and automobile tyres. Experimental results have shown that the ash and volatile contents of several recovered carbon blacks are high, the elongation at break of the vulcanised natural rubber filled with recovered carbon blacks from motorcycle tyres is better than that from motorcycle tyres and standard carbon black 7#, while the other mechanical properties are worse. In order to improve the reinforcing effect of recovered carbon blacks, the modification of recovered carbon black was performed by high-energy electron bombardment and non-oxidising acid. The specific surface area of the pyrolytic carbon blacks increased after high-energy electron bombardment. The ash content of the pyrolytic carbon black was reduced from 22.5% to 8.4% after rinsing with hydrochloric acid, and the tensile stress at 300% was increased by about 2.2 MPa.

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Transient absorption in fused silica induced by trains of high-energy electron pulses

Chemical Physics Letters ◽

10.1016/j.cplett.2005.09.089 ◽

2006 ◽

Vol 417 (1-3) ◽

pp. 170-172 ◽

Cited By ~ 3

Author(s):

E. Janata

Keyword(s):

Transient Absorption ◽

High Energy ◽

Fused Silica ◽

Energy Electron ◽

High Energy Electron ◽

Electron Pulses

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Kinematic Approximations in TED and RHEED Analysis of Reconstructed Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135587 ◽

1990 ◽

Vol 48 (2) ◽

pp. 396-397

Author(s):

L. -M. Peng ◽

M. J. Whelan

Keyword(s):

Electron Diffraction ◽

Kinematic Analysis ◽

Incident Beam ◽

High Energy ◽

Energy Electron ◽

Great Success ◽

High Energy Electron ◽

Kinematic Approximation ◽

Reconstructed Surfaces

In recent years there has been a trend in the structure determination of reconstructed surfaces to use high energy electron diffraction techniques, and to employ a kinematic approximation in analyzing the intensities of surface superlattice reflections. Experimentally this is motivated by the great success of the determination of the dimer adatom stacking fault (DAS) structure of the Si(111) 7 × 7 reconstructed surface.While in the case of transmission electron diffraction (TED) the validity of the kinematic approximation has been examined by using multislice calculations for Si and certain incident beam directions, far less has been done in the reflection high energy electron diffraction (RHEED) case. In this paper we aim to provide a thorough Bloch wave analysis of the various diffraction processes involved, and to set criteria on the validity for the kinematic analysis of the intensities of the surface superlattice reflections.The validity of the kinematic analysis, being common to both the TED and RHEED case, relies primarily on two underlying observations, namely (l)the surface superlattice scattering in the selvedge is kinematically dominating, and (2)the superlattice diffracted beams are uncoupled from the fundamental diffracted beams within the bulk.

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