  The results from an X-ray spectral analysis of a large sample of quasars,
observed with ASCA, are presented. Data reduction leaves 62 quasars, 35
radio-loud and 27 radio-quiet, suitable for spectral analysis. Differences are
found between the radio-quiet quasars (RQQs) and the radio-loud quasars (RLQs),
in agreement with previous studies. A correlation between Gamma and optical
H-beta was also found for the radio-quiet quasars in this sample, whereby the
steepest X-ray spectra tend to be found in those objects with narrow H-beta
widths. The correlation is significant at >99% confidence, confirming the
well-known trend between Gamma and H-beta FWHM in Seyfert 1s (Brandt et al.
1997), but at higher luminosities. Other spectral complexities are observed
from this sample. A soft X-ray excess, with blackbody temperatures in the range
100 - 300 eV, is seen in many low z radio-quiet quasars. In most cases the
temperatures are probably too hot to originate directly from the disk. Iron K
line emission features are also found in the RQQs; but often from partially
ionised material. Indeed in the highest luminosity RQQs there is neither
evidence for iron line emission nor the reflection component expected from disk
models. These observations can be explained by an increase in the quasar
accretion rate with luminosity, leading to an increase in the ionisation state
of the surface layers of the disk. The occurrence of ionised or `warm'
absorbers is rare in this sample, with only 5 detections. However excess
neutral X-ray absorption is found towards several of the high z, predominantly
radio-loud, quasars. Although found to increase with quasar redshift, this
`intrinsic' absorption may be associated with radio-loud AGN.
