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随着对植物辐射研究兴趣的增加及辐照植物材料的商品化应用,对植物组织内剂量分布模式的估计正日益受到重视。当用块茎等松散的组织材料或较大包装体积的谷物及花粉来研究几百拉德数量级剂量效应时,这种估计显得更加重要。在所有情况下,射线穿过物质时,伴随着能量传递,而该物质的厚度、密度和化学组成都将影响组织内的剂量分布。辐射率在组织内的减弱用减弱系数 e~(-(μ/ρ·ρ·x))表示,其中μ/ρ是质量减弱系数,单位是 m~2·kg~(-1),ρ是密度,单位是 kg·m~(-3),x 是组织厚度,单位是 m。组织的厚度和密度可以测量。质量减弱系数可根据有效原子序数 Z 确定,这里应考虑植物材料中主要物质的相对重量及它们的原子序数(Z)与原子量(A)的比值。根据减弱系数的意义可以用表达式 D=B·D_0·e~(-(ρ/ρ·ρ·x))计算靶组织一定深度的吸收剂量
With the increasing interest in research on plant radiation and the commercial application of irradiated plant material, the estimation of the dose distribution pattern in plant tissues is increasingly valued. This estimate is even more important when studying bulk dose effects on the order of a few hundred Radians with loose tissue material such as tubers or larger packed volumes of grain and pollen. In all cases, the ray travels through the substance accompanied by energy transfer, and the thickness, density and chemical composition of the substance will affect the dose distribution within the tissue. The attenuation of emissivity in the tissue is expressed by the attenuation coefficient e ~ (- (μ / ρ · ρ · x)), where μ / ρ is the mass attenuation coefficient in units of m ~ 2 · kg -1, ρ is Density in kg · m ~ (-3), x is the thickness of the tissue, the unit is m. Tissue thickness and density can be measured. The coefficient of mass loss can be determined from the effective atomic number Z, where the relative weight of the major species in the plant material and the ratio of their atomic number (Z) to the atomic weight (A) should be considered. According to the significance of the attenuation coefficient, the absorbed dose of the target tissue at a certain depth can be calculated by the expression D = B · D_0 · e ~ (- (ρ / ρ · ρ · x)