順酐，也稱為馬來酸酐或失水蘋果酸酐，是一種具有強烈刺激氣味的白色晶體。它的化學式為C4H2O3。順酐可以溶于乙醇、乙醚和丙酮，但在石油醚和四氯化碳中難溶。它與熱水反應形成馬來酸。此外，順酐還應用于多個領域，包括但不限于不飽和聚酯樹脂、醇酸樹脂、農藥、涂料、潤滑劑添加劑、造紙化學品、紡織品整理劑、食品添加劑以及表面活性劑等。

Maleic anhydride, also known as maleic anhydride or dehydrated malic anhydride, is a white crystal with a strong pungent odor. Its chemical formula is C4H2O3. Maleic anhydride can be soluble in ethanol, ether, and acetone, but it is difficult to dissolve in petroleum ether and carbon tetrachloride. It reacts with hot water to form maleic acid. In addition, maleic anhydride is also applied in multiple fields, including but not limited to the production of unsaturated polyester resins, alkyd resins, pesticides, coatings, lubricant additives, papermaking chemicals, textile finishing agents, food additives, and surfactants.

順酐的結晶點是指順酐從液體狀態轉變為固體狀態時的溫度,也是一種反映順酐純度的指標。順酐結晶點的高低會直接影響到順酐的質量和效率,因此進行結晶點分析及控制是工業過程中的重要環節。

The crystallization point of maleic anhydride refers to the temperature at which it transitions from a liquid state to a solid state, and is also an indicator of the purity of maleic anhydride. The high or low crystallization point of maleic anhydride directly affects the quality and production efficiency of maleic anhydride. Therefore, analyzing and controlling the crystallization point is an important link in the industrial production process.

順酐結晶點的測試所需儀器如下：

The required instruments for testing the crystallization point of maleic anhydride are as follows:

1. 全自動結晶點測定儀SH406。

1. Fully automatic crystallization point tester SH406.

2. 結晶點專用試管。

2. Crystal point dedicated test tube.

實驗步驟如下：

The experimental steps are as follows:

①把樣品如試管后，點擊觸摸屏對樣品進行升溫加熱。

① After turning the sample into a test tube, click on the touch screen to heat up the sample.

②液體試樣量到結晶點試管的刻度線處。

② Measure the liquid sample to the mark on the crystallization point test tube.

③把傳感器插入對應的儀器插口處。

③ Insert the sensor into the corresponding instrument socket.

④把傳感器套裝插入試管內，將試管放入儀器中。

④ Insert the sensor kit into the test tube and place the test tube into the instrument.

⑤點擊觸摸屏，進入“參數設置”，設置：“預期結晶點”“試樣編號”，設置完成后返回主界面。

⑤ Click on the touch screen to enter "Parameter Settings", set "Expected Crystallization Point" and "Sample Number". After setting, return to the main interface.

⑥在“主界面”，點擊“開始”進行實驗。

⑥ In the main interface, click "Start" to conduct the experiment.

⑦實驗完成后，自動出結果，自動打印，數據可通過U盤導出。

⑦ After the experiment is completed, the results will be automatically generated, printed, and the data can be exported through a USB drive.