24 C si(111) 如 04 Rotation Angle(second Figure 7. Rocking curves of the double-crystal diffractometer including various breast tissues taken with the 9 keV x-ray. There are obvious differences between these rocking curves taken with or without various tissues Table 1. The peak displacement, reflected intensity and FWHM of the rocking curve of the double-crystal diffractometer with different breast tissues and 9 keV x-ray. Peak displacement (s) FWHM (s) Reflected intensity Double-crystal 0.00 Normal breast 0.381 (9.00±006)0.33200.43±0.07) ouble-crystal 0.2 Benign breast -0.2 0.498 tumour tissue (-0.15±0.08) 917(9.16±0.08)0.763(0.66±0.09) double-crystal -0.2 -0.2 0.633 cancer 0.594 (0.00±0.16 9.14(8.97±0.07)0.413(0.50±0.10)449 diffractometer 0.2 8.96 0.678 Data in parentheses are the average values. can provide the absorption and extinction information. Its contrast will not be seriously affected by the scattering because those scatters are out of the rocking curve, which is the extinction effect. In other words, the small-angle scattering is rejected from the peak images The contrast of peak images can be enhanced by virtue of the extinction effect. Therefore, some new structures will be seen in the peak images. For example, the fibril of normal breast tissue with a diameter of about 30 um( see figure 1(A), the benign tumour with a sharp edge(see figure 1(B))and the sheets of calcifications(formed by calcified spots of tens of micrometres)of malignant breast tissue(see figure I(C) are shown in those peak image424 C Liu et al Figure 7. Rocking curves of the double-crystal diffractometer including various breast tissues taken with the 9 keV x-ray. There are obvious differences between these rocking curves taken with or without various tissues. Table 1. The peak displacement, reflected intensity and FWHM of the rocking curve of the double-crystal diffractometer with different breast tissues and 9 keV x-ray. Integrated Peak displacement (s) FWHM (s) Reflected intensity intensity Double-crystal 0.00 8.37 1.00 8.37 diffractometer Normal breast 0.2 8.96 0.381 tissue + 0.2 (0.25 ± 0.08)a 8.97 (9.00 ± 0.06) 0.332 (0.43 ± 0.07) 3.87 double-crystal 0.2 9.13 0.522 diffractometer 0.4 8.96 0.477 Benign breast −0.2 9.18 0.498 tumour tissue + 0.0 (−0.15 ± 0.08) 9.17 (9.16 ± 0.08) 0.763 (0.66 ± 0.09) 6.05 double-crystal −0.2 9.00 0.734 diffractometer −0.2 9.30 0.633 Breast cancer 0.2 8.80 0.594 tissue + 0.0 8.97 0.392 double-crystal −0.2 (0.00 ± 0.16) 9.14 (8.97 ± 0.07) 0.413 (0.50 ± 0.10) 4.49 diffractometer 0.2 8.97 0.567 −0.2 8.96 0.678 a Data in parentheses are the average values. can provide the absorption and extinction information. Its contrast will not be seriously affected by the scattering because those scatters are out of the rocking curve, which is the extinction effect. In other words, the small-angle scattering is rejected from the peak images. The contrast of peak images can be enhanced by virtue of the extinction effect. Therefore, some new structures will be seen in the peak images. For example, the fibril of normal breast tissue with a diameter of about 30 µm (see figure 1(A)), the benign tumour with a sharp edge (see figure 1(B)) and the sheets of calcifications (formed by calcified spots of tens of micrometres) of malignant breast tissue (see figure 1(C)) are shown in those peak images