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本文描述用２４１Ａｍ和１３７Ｃｓ两个放射源从同一铅屏蔽容器和准直器射出两种能量的γ射线窄束，穿透土壤样品后用ＮａＩ（Ｔｌ）多道γ谱仪测量６０和６６２ｋｅＶγ射线的峰感性区计数率，依据土壤和水对６０ｋｅＶγ射线的质量衰减系数有较大差异而对６６２ｋｅＶγ射线的质量衰减系数基本相同的特点，测定了土壤样品的密度和水含量。用某种土壤制作一系列已知土壤密度和水含量的标准样品，用这种双能量γ射线穿透法分别测量６０和６６２ｋｅＶ的γ射线透射率，用最小二乘法拟合土壤密度和水含量与穿透率的函数表达式，用这些表达式测量由用户制备的已知该类土壤密度和水含量的样品，测试结果满足了用户的需要。
In this paper, two γ-ray narrow beams of two energies are emitted from the same lead-shielding vessel and collimator using two sources of 241Am and 137Cs. After penetrating the soil samples, the 60 and 662 keV γ-rays were measured using a NaI (Tl) multichannel gamma spectrometer The count rate of the peak perceptual zone was determined according to the fact that the mass attenuation coefficient of 60 keV gamma rays was significantly different between soil and water, and the mass attenuation coefficient of 662 keV gamma rays was basically the same. The density and water content of the soil samples were determined. A series of standard samples with known soil densities and water contents were prepared from some soils and the γ-ray transmissivity was measured at 60 and 662 keV, respectively, using this dual-energy gamma-ray penetration method. The least square method was used to fit the soil densities and water contents And the permeability of the functional expression, using these expressions to measure the user-made samples of this known soil density and water content, the test results to meet the needs of users.