X-ray spectra analysis from K-absorption edge to maximum energy for the improvement of IVR low-contrast

(1)比较水和丙烯酸树脂的X射线能谱，结果表明，丙烯酸树脂的X射线跃迁比在低能量比时较高，在高能比时较低。当使用丙烯酸树脂时，这是一个值得考虑的问题。(2)当插入由铝、铜、Nb和钼制成的滤光片时，发现使用这些滤光片可以获得衰减比，就像利用质量衰减系数(Hubbell提出的质量衰减系数)计算衰减比一样，而不进行剥离校正。Nb和Mo滤光片的加入减少了较低能量X射线的光子，并传输了高能X射线的光子。添加Al滤光片有一定的效果，但不明显，而添加铜滤光片的效果介于Nb或Mo和Al之间。(3)还测量了滤光片的X射线透过率。对于40keV到70keV的范围，正色屏幕应该减少X射线的光子，但对于其他范围，规则屏幕应该减少光子。

A examination of X-ray spectra analysis for the improvement of clinical technique and X-ray equipment was conducted.(1)A comparison of X-ray spectrum of the water and acrylic resin showed that the X-ray transisslon ratio of acrylic resin was high for low energy resions, and low for high energy resions. This constitutes a sonsiderable problem when acrylic resin is used.(2)When filters made of aluminum, copper, niobium and molybdenum were Inserted, It was found that the attenuation ratios could be obtained with these filters as If the attenuation ratio was ca1culated by using mass attenuation coefficients (which have been suggested by Hubbell) without stripping correction. The addition of the Nb and Mo filters reduced In the photons of lower X-ray energy, and transmitted the photons of high-energy X-rays. The addition of the Al filter tended to have the effect, but less evident, while the effect of the Cu filter was between that of Nb or Mo and of Al.(3)The X-ray transmission, ratio of the screen was also measured. For the range from 40 keV to 70 keV, the orthochromatic screen should reduced the photons of X-ray, - but for anly other range the regular screen should reduced the photons.