The Shanghai Jiezhun TGA-1150 thermogravimetric analyzer assists in measuring the decomposition weight loss and decomposition heat of calcium oxalate at the School of Materials Science and Technology, East China University of Science and Technology.Thermogravimetric analysis is a technique for measuring the relationship between material mass and temperature under program-controlled temperature. The curve obtained from the thermogravimetric experiment is called thermogravimetric analysis（TG）Curve.TGThe curve shows a series of changes in the absolute mass of the sample with a constant increase in temperature, with temperature as the horizontal axis and the weight loss of the sample as the vertical axis. These changes characterize the volatilization of volatile components in the sample at different temperature ranges, as well as the volatilization of decomposition products at different temperature ranges. As shown in the figure1, picture2 CaC2O4·H2OThe thermogravimetric curve shows three distinct stages of weight loss. The first stage represents the loss of water molecules, and the second stage representsCaC2O4decompose intoCaCO3The third stage representsCaCO3decompose intoCaOOf course,CaC2O4·H2OThe thermogravimetric analysis is quite typical, and in reality, the thermogravimetric curves of many substances may not be clearly distinguished into different stages, and may even become a continuously changing curve. At this point, it becomes particularly important to determine the rate of change of the curve within various temperature ranges. It is the first derivative of the thermogravimetric curve, known as the differential thermogravimetric curve[picture1It also shows thatCaC2O4·H2OThe differential thermogravimetric curve（DTG）]The differential thermogravimetric curve can effectively display these rate changes.