Thermogravimetric Loss Data of Typical Black Soil Profile in Northeast China

Soil thermogravimetric analysis was completed using the THEMYSH2 analyzer (SETARAM Instruments, France). After air drying and grinding, the soil sample is sieved through a 100 mesh sieve, and the amount used for determination is approximately 60 mg. The measurement conditions are as follows: use an alumina crucible, with a temperature range of room temperature to 700 ℃, and a heating rate of 5 ℃ · min-1. To eliminate errors caused by hysteresis effect, heat at a constant temperature for 15 minutes when the temperature is raised to 125 ℃. The protective gas is 20 mL · min-1 argon gas, and the purge gas is 20 mL · min-1 pure air. The thermogravimetric data is output every 10 ℃ of heating, and the difference between adjacent two points is used to differentiate the heating temperature once, resulting in a derivative of thermogravimetry (DTG) curve that reflects the dynamic changes in the rate of mass loss of the sample during the heating process. Analyze and process the thermogravimetric loss data using R3.6.3 to obtain the mass loss in the low-temperature and high-temperature sections, and calculate their ratio and temperature at 50% weight loss.

采用法国塞塔拉姆仪器（SETARAM Instruments）公司的THEMYSH2型热重分析仪完成土壤热重分析。土样经风干、研磨后过100目筛，用于测定的样品质量约为60 mg。测试条件设置如下：使用氧化铝坩埚，温度区间为室温至700 ℃，升温速率为5 ℃·min⁻¹；为消除滞后效应引入的测试误差，当升温至125 ℃时，恒温保持15分钟。保护气为流量20 mL·min⁻¹的氩气，吹扫气为流量20 mL·min⁻¹的纯空气。热重数据每升温10 ℃输出一次，通过对相邻测点的质量变化进行一次温度微分运算，得到导数热重（DTG，derivative thermogravimetry）曲线，该曲线可反映样品在升温过程中质量损失速率的动态变化。采用R3.6.3软件对热重损失数据进行分析与处理，获取低温段与高温段的质量损失量，计算二者的比值以及样品失重50%时对应的温度。