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With the detrended fluctuation analysis, we investigate dynamics of human brain electroencephalogram. Long-range temporal correlation and scaling behavior are observed, and certain characteristic of the Alzheimer's disease is revealed.

Compton scattering of gamma-rays, XRD, TEM and Raman scattering were used to investigate the nanocrystalline graphite produced by mill grinding. The graphite ground for 4 and 8 hours has a typical nanostructure. Further grinding produces a mixture of nanocrystalline and amorphous phases. Compared with the polycrystalline graphite, the electron momentum distribution probability (EMD) of nanocrystalline graphite is a little higher in the low momentum range. We attribute such a change mainly to the high interface ratio of nanograined graphite.

Using a Compton polarization analyzer the linear polarization of one photon from the three-photon decay of orthopositronium under several geometrical conditions has been measured. For α 1 =45°, 75°, 105° and 120°, the ration of the number of photons Compton-scattered parallel to the plane of the three photons to the number scattered perpendicular to that plane was found to be 1.20±0.03, 1.53±0.03, 1.76±0.06 and 1.86±0.06, respectively. The linear polarization of the photons along the plane of the three photons was determined as 0.15±0.04, 0.33±0.04, 0.49±0.04 and 0.51±0.05, respectively. This result is in agreement with theoretical predictions.