TGA and DTA curves of stepwise decomposition of calcium oxalate monohydrate, sample mass 19mg, heating rate 30K/min, nitrogen atmosphere. The TGA curve has been normalized and therefore begins at 100%. The temperature range of the three weightlessness steps is particularly clear on the first-order derivative DTA curve. At 120 ℃, calcium oxalate monohydrate loses its crystalline water. Continuing to heat up, anhydrous calcium oxalate decomposes in two steps.

When the sample loses substances in different ways or reacts with the environmental atmosphere, the mass changes, resulting in steps on the TGA curve and peaks on the DTA curve. There are many different effects that can cause the sample to lose or gain mass, such as

2. Evaporation and drying of volatile components, desorption and adsorption of gases, moisture, and other volatile substances, and loss of crystalline water;

3. Oxidation of metals in air or oxygen;

4. The oxidation and decomposition of organic matter in air or oxygen;

5. Thermal decomposition in an inert atmosphere is accompanied by the generation of gases. For organic compounds, this process is called pyrolysis;

6. Heterogeneous reactions between the sample and the atmosphere, such as reduction reactions with hydrogen containing purge gases.

The magnetic properties of some materials change with temperature and undergo Curie transition. If these materials are tested in a non-uniform magnetic field, the change in magnetic attraction at the Curie transition will produce a TGA signal.

TGA detectable material properties

Technical parameters:

1. Temperature range: Room temperature~1150 ℃
2. Temperature resolution: 0.1℃
3. Temperature fluctuations: ±0.1℃
4. Heating rate: 1~80℃/min
5. Temperature control methods: heating, constant temperature, cooling
6. Cooling time: 15min (1000℃…100℃)
7. Measurement range of balance: 1mg～2g
8. Resolution: 10μg
9. Constant temperature time: 0-300min arbitrary setting
10. Display mode: Chinese character large screen LCD display
11. Atmosphere device: Built in gas flow meter, including two-way gas switching and flow rate control

(Atmosphere: Inert, oxidizing, reducing, static, dynamic)

12. Software: Automatically record TG curves for data processing and print experimental reports
13. Data interface: USB interface, dedicated software
14. Power supply: AC220V 50Hz

Some basic knowledge about our TGA thermogravimetric analyzer:

1. How long does it take for the balance of a thermogravimetric analyzer to stabilize?

Answer: The balance needs to stabilize for 2 hours after turning on the machine

2. What is the content of the thermogravimetric curve chart?

Answer: The horizontal axis displays T (temperature), and the vertical axis displays the percentage of thermal weight loss

3. Is the stability of the balance determined by human recognition or machine recognition after sample injection?

Answer: Human recognition

4. Can we determine the temperature of a point on the y-axis that represents the percentage of thermal weight loss?

Answer: Yes, it is possible

5. Can TGA perform first-order differentiation to obtain DTG curve?

Answer: Yes, it is possible, The DTG line will not be directly displayed, and after the experiment is completed and calculated, the DTG curve can be obtained.

6. How long does it take to drop from 1000 ℃ to room temperature?

Answer: About 1 hour

7. Is the atmosphere oxygen or nitrogen?

Answer: Yes

8. Is there a combination of TGA and DSC available

Answer: Some