Correct operation process of melting point meter:

1. Parameter settings

Temperature range: The starting temperature should be 5-10 ℃ lower than the expected melting point (conventional measurement) or 20-30 ℃ (microscopic method); The termination temperature is above 10 ℃ above the melting point. For example, the range of unknown samples can be appropriately expanded to capture the complete melting process;

Heating rate: Conventional measurement uses 1 ℃/minute; Use 0.5 ℃/min for precision testing or purity analysis; Mixing melting points or easily decomposable samples can be adjusted to 5-10 ℃/min to improve efficiency.

2. Installation and startup

Place the sample: Place the capillary tube/slide containing the sample in the center of the heating table to ensure uniform heating and resistance to displacement; The micro melting point analyzer needs to adjust the focal length to make the sample image clear and visible;

Start program: Press the "Start" button to start heating up. Some automation devices support real-time display of melting curves or automatic photography to record morphological changes.

3. Observation and recording

Initial melting point judgment: Observe the crystal edge becoming rounded, droplets appearing, or sudden changes in transparency (automatically recognized by photoelectric detection instruments), and record the temperature at this time as the initial melting point;

Full melting confirmation: Stop heating when the sample is completely liquefied, changes color (such as transparent to orange), or loses its solid structure, which is recorded as the final melting temperature;

Multiple validation: Repeat the same sample 2-3 times and take the average to reduce accidental errors; If there is a significant difference in the results, it is necessary to check the purity of the sample or recalibrate the instrument.

End and maintenance of melting point meter:

1. Cooling and cleaning

Turn off the device: After the test is completed, turn off the power in a timely manner and wait for the heating table to cool naturally to room temperature before taking out the sample to avoid glass breakage or burns to the operator due to temperature differences;

Remove residue: Use tweezers to remove the cover glass, wipe the surface of the glass slide and heating table with alcohol swab to remove any residue; Regularly clean the interior of the melting point tube to prevent carbon buildup from affecting heat transfer efficiency.

2. Data management and maintenance

Save Report: Automatically print or export test reports with melting curves, indicating initial/final melting temperatures and experimental conditions; Manual recording should include a description of changes in sample status (such as decomposition, discoloration, and other abnormal phenomena);

Regular maintenance: Check the tightness of power cord connections, sensor sensitivity, and lubrication of mechanical transmission components; Store in a dry environment when not in use for a long time to avoid mold growth of optical components.