弹性模量越大,材料越不容易变形,且()。 ["刚性越强、硬度越大","刚性越弱、硬度越小","刚性越强、硬度越小","刚性越弱、硬度越大"]
()是材料发生单位应变时的应力,它表征材料抵抗变形能力的大小。 ["拉伸模量","杨氏模量","切变模量","弹性模量"]
在一定温度、恒定应变的条件下,试样内产生的应力随时间延长而逐渐减小的现象称() ["蠕变","应力松弛","滞后","力学内耗"]
以EDTA法测定某试样中MgO(其摩尔质量为40.31g/mol)含量,用0.02mol/LEDTA滴定.设试样中含MgO约50%,试样溶解后容成250ml,吸取25ml进行滴,则试样称取量应为:() ["0.1~0.2g","0.16~0.32g","0.3~0.6g","0.6~0.8g","0.8~1.2g"]
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互生作用