Preparation before verification: ensure that basic conditions are met

Before calibrating the calorimeter, you need to be fully prepared. First, check whether the appearance of the calorimeter is in good condition, whether the connections of various components are stable, and the power supply and wiring are not damaged. At the same time, ensure that the laboratory environment is stable, the temperature is controlled at 15-30 ° C, and the humidity is maintained at 40% -60% to avoid environmental factors interfering with the calibration results. In addition, prepare a reference material, such as benzoic acid, whose calorific value is known and stable, which is a key reference for calibration.

Core verification steps: accurately control key links

1. Instrument preheating and initialization: Turn on the calorimeter and let it preheat for at least 30 minutes. After the instrument is stable, initialize the settings according to the operation process, calibrate the instrument zero point and baseline, and ensure that the measurement start state is accurate.

2. Standard substance test: accurately weigh an appropriate amount of standard benzoic acid, put it in a combustion dish, and place it in a calorimeter according to the specifications. Start the test program and record the temperature change before and after combustion and other data. Repeat the test several times, generally no less than 5 times, and take the average value to reduce accidental errors.

3. Data calculation and comparison: Calculate the measured calorific value of the reference material based on the principle of the calorimeter and test data. Compare it with the standard calorific value. If the error is within the specified range (usually ± 0.2%), it indicates that the accuracy of the instrument is up to standard; if it exceeds the range, the instrument needs to be checked and adjusted.

Post-calibration maintenance: ensuring long-term stability of the instrument

After the calibration is completed, clean up the combustion residue in time to keep the inside of the instrument clean. Maintain the key components of the instrument, such as regularly changing the sealing ring, cleaning the sensor, etc. At the same time, record the calibration process and results, and establish an instrument calibration file to facilitate subsequent tracking of instrument performance changes.

Through the above steps, the calorimeter can be scientifically and accurately calibrated to ensure accurate measurement, providing reliable data support for experimental and testing work.