Fourier transform infrared spectrometerThe core performance of FTIR relies on the stability of the optical system and detector, and scientific maintenance can extend the lifespan of core components by more than 30%, ensuring the accuracy of spectra. The following outlines key techniques from four aspects: core components, environmental control, daily maintenance, and regular calibration.
Core component maintenance is of utmost importance. In terms of light sources, infrared light sources such as silicon carbide rods have a lifespan of about 2000 hours and require the establishment of a usage ledger. After a cumulative usage of 1800 hours, they should be replaced as backup. When replacing, the power should be turned off for cooling to avoid burns caused by high-temperature operations. If the detector is of MCT type, it is necessary to check the liquid nitrogen level daily. If it is lower than 1/3, it should be replenished in a timely manner. When replenishing, wear anti cold clothing and gloves to prevent liquid nitrogen splashing and frostbite; Semiconductor refrigeration detectors need to regularly clean the heat dissipation holes to avoid dust accumulation and reduce refrigeration efficiency. It is strictly prohibited to disassemble the interferometer by oneself. Every quarter, perform "interferogram calibration" through operating software to ensure peak symmetry. If distortion occurs, immediately contact the manufacturer.
Environmental control is the fundamental guarantee. The laboratory needs to maintain a constant temperature of 18 ℃ -25 ℃ (fluctuation ≤ ± 1 ℃) and a constant humidity of 30% -60%. A dehumidifier should be installed during the humid season, and the desiccant replacement cycle can be shortened during the rainy season. The equipment should be kept away from vibration sources such as centrifuges and ultrasonic cleaning machines, with a distance of ≥ 1.5m, to avoid displacement of the interferometer reflector; Stay away from high-power equipment and equip with a regulated power supply to prevent voltage fluctuations from damaging the circuit. Blow the ventilation openings of the main unit with 0.2MPa compressed air every month, and wipe the sample room with a dust-free cloth after each use to prevent residual corrosion of optical components.
Daily maintenance requires attention to details. Desiccant should be checked monthly, and the silicone gel should be replaced immediately if it changes color. Quick operation should be carried out during replacement to reduce water vapor infiltration. Thoroughly clean the sample accessories after each use: wipe and dry the tablet mold with anhydrous ethanol, and gently wipe the window panel with lens paper dipped in acetone in the forward direction, avoiding back and forth wiping and scratching; After ultrasonic cleaning, dry the sealed pool to avoid cross contamination. When idle, it is necessary to preheat the capacitor for 30 minutes every week to prevent aging. Place a new desiccant in the sample room and cover the window with a dust cover.
Regular calibration cannot be ignored. Every year, CNAS qualification institutions are commissioned to calibrate, with a focus on verifying wavelength accuracy and resolution; Use standard materials (such as polystyrene film) for verification every half a year. If the characteristic peak deviation exceeds ± 1cm ⁻⁻⁻, contact after-sales for adjustment in time. Establish and maintain archives to record replacement, calibration, and fault information, providing a basis for equipment status traceability.