中文摘要：

为了利用模型模拟实际的吸附过程，以BET等温式为基础，应用统计热力学方法，在多层吸附过程中满足相邻两层间的化学势相等、气相中的吸附势与吸附相中第m层的化学势相等及相变平衡时气一液两相化学势相等的条件，建立了吸附等温线理论模型。利用吸附仪对含PdO的吸气剂在77K下进行实验研究，再结合BET二常数公式和理论模型，获得单分子层饱和吸附量、吸附常数和吸附层数。在此基础上，选取基松势能函数表示气体分子之间的相互作用，求解模型，并将结果与实验数据进行对比。相对压力小于0．05时，理论计算值低于实验值；相对压力为0．05，0．9的范围内，理论模型与实验数据吻合得较好；相对压力大于0．9后，理论计算值高于实验值。对比结果表明含PdO的吸气剂在77K下的吸附属于物理吸附。

英文摘要：

The adsorption of the PdO-containing getter at 77 K, in high vacuum insulation cryogenic vessel was modeled, based on Brunauer- Emmett-Teller （BET） , s isotherm and statistic thermodynamics. The adsorption isotherm model is valid under the conditions： the adjacent layers have identical chemical potential, the gas-phase adsorption potential equals to the layer＇ s chemical potential in adsorbed phase, and the gas phase has the same. adsorption potential as the liquid phase in gas-liquid equilibrium. The adsorption of the PdO-containing getter at 77 K was measured, The saturated adsorption capacity of one monolayer, adsorption constant, and adsorption layers were calculated and experimentallymeasured. Since Keesom potential function describes the interaction of gas molecules, theadsorption isotherm equation could be solved. The results show that N2 was physisorbed to the PdO-containing getter at 77 K, and that at a partial pressure ranging from 0. 05 to 0. 9 , the calculated adsorption capacities of nitrogen agrees fairly well with the measured ones.