Use peaks with large 20 0.030 0.025 0.05°-9 0.01°-A9 8 0.020 0.015 0.005°-9 p/pV 0.010 0.005 0.001°-A9 0.000 30405060708090 0() 点阵参数测量精度与和△的关系30 40 50 60 70 80 90 0.000 0.005 0.010 0.015 0.020 0.025 0.030 d/d , %  0.010 ~ 0.050 ~ 0.0050 ~ 0.0010 ~ 点阵参数测量精度与 θ 和Δθ的关系 Use peaks with large 2 