Conducting and Antistatic Composites for Space Applications

2004 ◽  
Vol 851 ◽  
Author(s):  
Mircea Chipara ◽  
Jagannathan Sankar ◽  
Petre Notinger ◽  
Denis Panaitescu ◽  
David Hui ◽  
...  

ABSTRACTThe percolative dependence of the DC conductivity on the volume concentration of fillers for composites obtained by dispersing conducting particles into polymeric matrices is studied in detail. An empirical Boltzmann like dependence is proposed for the modeling of the dependence of DC conductivity versus filler concentration. This expression allows for a more accurate determination of the percolation threshold in the case of broad percolations. It is shown that the loading of the polymeric matrices with conducting fillers produces percolative-like changes of various physical properties (such as the reciprocal of the tensile strength and the reciprocal of the double integral of the resonance spectrum). Experimental mechanical, electrical, and electron spin resonance data on polyvinylchloride-carbon, polyvinylchloride-polyaniline, and polyethylene-polyaniline composites are reported.

Author(s):  
Brian Burton ◽  
Thomas A. Claxton ◽  
Stephen J. Hamshere ◽  
Howard E. Marshall ◽  
Richard E. Overill ◽  
...  

1977 ◽  
Vol 8 (10) ◽  
pp. no-no
Author(s):  
B. BURTON ◽  
T. A. CLAXTON ◽  
S. J. HAMSHERE ◽  
H. E. MARSHALL ◽  
R. E. OVERILL ◽  
...  

1977 ◽  
Vol 55 (19) ◽  
pp. 3356-3363 ◽  
Author(s):  
William Arthur Seddon ◽  
John Wallace Fletcher ◽  
Fred Charles Sopchyshyn ◽  
Ron Catterall

Pulse radiolysis of tetrahydrofuran (THF), dimethoxyethane (DME), diglyme (DG), and triglyme (TG), results in the formation of solvated electrons, es−, with optical band maxima λmax ≥ 1840 nm. In the presence of alkali metal salts transient optical bands are observed with λmax at ∼900 and ≥1600 nm. The latter bands are assigned to the formation of 'monomeric' species of stoichiometry M considered to be 'tight' and 'loose' ion-pairs, respectively. The proportion of 'loose' ion-pairs increases with decreasing temperature and increasing coordination of the solvent in the order [Formula: see text] These results demonstrate a good correlation with established electron spin resonance data in alkali metal solutions and substantiate the coexistence of at least two 'monomeric' species in DME and the glymes.


1987 ◽  
Vol 95 ◽  
Author(s):  
Z E. Smith ◽  
S. Wagner

AbstractThe experimental phenomena associated with light-induced degradation and thermal recovery of hydrogenated amorphous silicon (a-Si:H) films are reviewed, with special emphasis on the limitations of each experimental technique. When several techniques are used in concert, a fuller picture emerges. Recent experiments suggest different positions in the band-gap of the paramagnetic-associated defect states (the dangling bonds) for doped and undopedfilms; this information can be combined with conductivity, sub-bandgap optical absorption and electron spin resonance data to yield a model for the density of gap states (DOS) in a- Si:H, including how the DOS changes upon illumination and annealing.


2011 ◽  
Vol 62 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Pavle Premović ◽  
Budimir Ilić ◽  
Dragan Đorđević

A new method for determining the concentration of vanadyl ions in claysA novel and simple method for quantitatively determining the concentration of vanadyl ions in clays using electron spin resonance data has been developed. Several vanadyl standards with concentrations between 200-1000 ppm were prepared in a mixture of glycerol and kaolinite (KGa-2). The anisotropic electron spin resonance (ESR) spectra were recorded at room temperature, and the specific intensity of the line (attributed to nuclear spin m = -5/2||) was determined. For vanadyl concentrations between 50 ppm and 200 ppm, the standards must be prepared by mixing kaolinite with known vanadyl content (FBT2A-03) and kaolinite (GB1) containing no vanadyl. The method is applicable without modification to other clays and clay-rich sediments containing vanadyl ions. The whole procedure is very suitable for routine work.


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