Probing the structure of an amorphous solid : proof from Compton scattering measurements that amorphous carbon is predominantly graphitic

For x-ray scattering from amorphous media at large sin θ/λ (> 1.00 Å-1) momentum and energy is either imparted to a single electron (Compton effect) or to a single atom (Thermal Spike effect). In both cases the impulse approximation provides a convenient method for treating the scattering. Measurements of the ratio of Thermal Spike scattering to Compton scattering were made on paraffin.

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The resonant scattering of gamma radiation from lead isotopes

Canadian Journal of Physics ◽

10.1139/p78-134 ◽

1978 ◽

Vol 56 (8) ◽

pp. 1021-1036 ◽

Cited By ~ 8

Author(s):

J. W. Knowles ◽

A. M. Khan ◽

W. F. Mills

Keyword(s):

Gamma Radiation ◽

Compton Scattering ◽

Scattered Radiation ◽

Lead Isotopes ◽

Resonant Scattering ◽

Aluminum Plate ◽

Γ Radiation ◽

Energy Beam ◽

Scattering Measurements ◽

Variable Energy

The scattering of gamma radiation from different isotopic mixtures of lead has been measured between 4.7 and 8.3 MeV with a variable energy beam with 175 keV resolution obtained by Compton scattering (n,γ) radiation of nickel from a curved aluminum plate. The elastically scattered radiation was detected with a 12.5 cm diameter, 12.5 cm long NaI(Tl) and with 27 or 49 cm3 Ge(Li) detectors located at scattering angles of 135° and 90°, respectively. Relative scattering measurements from targets of natural lead, radio-lead, and lead enriched in 208Pb show that the most prominent peaks of natural lead are in 208Pb at 7332.6 ± 1.3, 7087.7 ± 4.6, 7064.4 ± 3.5, 6721.0 ± 1.8, 5507.6 ± 1.8, 5292.6 ± 3.3, 4836.5 ± 4.6 keV. Measurements of resonant scattering and resonant self-absorption of the more intense scattered radiations provide information on level widths.

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Formation of cubic C-BN by crystallization of nano-amorphous solid at atmosphere

Journal of Materials Research ◽

10.1557/jmr.1998.0245 ◽

1998 ◽

Vol 13 (7) ◽

pp. 1753-1756 ◽

Cited By ~ 9

Author(s):

Bin Yao ◽

L. Liu ◽

W. H. Su

Keyword(s):

Solid Solution ◽

Grain Size ◽

High Pressure ◽

Boron Nitride ◽

Amorphous Carbon ◽

Solid Solutions ◽

Room Temperature ◽

Amorphous Solid ◽

High Energy ◽

High Pressure And Temperature

An amorphous carbon-boron nitride (C-BN) solid was prepared by ball milling the mixture of graphite and hexagonal BN powders for a period of 120 h. After annealing the amorphous C-BN solid for 1 h at atmosphere in the temperature range from 800 to 900 K and then quenching it to room temperature, a small amount of cubic C-BN solid solutions with diamond-like structure, which belong to a high energy phase and can only be synthesized previously under high pressure and temperature (30 GPa, 2000 K), were observed in the annealed amorphous C-BN solid. The lattice constant of the cubic C-BN solid solution was 0.3587 nm, and its grain size was in the range of 10 to 50 nm.

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