The UV spectrophotometer can arbitrarily select light of different wavelengths in the UV-visible region. The absorption spectrum of a substance is the result that the molecules and atoms in the substance absorb the light energy of certain specific wavelengths in the incident light, and the molecular vibrational energy level transition and the electronic energy level transition occur accordingly.
Since various substances have their own different molecules, atoms and different molecular spatial structures, their absorption of light energy will not be the same. Therefore, each substance has its own unique and fixed absorption spectrum curve, which can be judged or determined based on the absorbance at certain characteristic wavelengths in the absorption spectrum.
Precautions of UV vis spectrophotometer:
1. Take out the desiccant in the sample chamber before starting the machine. It is forbidden to open the sample chamber cover during the self-checking process of the instrument.
2. The solution in the cuvette should be 2/3～4/5 of the height of the cuvette, and it should not be too full to prevent the liquid from overflowing and corroding the instrument. Keep the cuvette clean during the measurement, and wipe the liquid droplets on the wall with lens cleaning paper. Do not pinch the translucent surface with your hands. When measuring the ultraviolet wavelength, a quartz cuvette is required.
3. During the measurement, it is forbidden to put reagents or liquid substances on the surface of the instrument. If the UV-Vis spectrophotometer has solution overflow or other reasons, the sample tank should be cleaned up as soon as possible.
4. After the experiment, pour out the solution in the cuvette, then rinse the cuvette with distilled water or organic solvent until it is clean, and dry it upside down. Turn off the power, put the desiccant into the sample chamber, cover the dust cover, and register for use.
FAQ of UV VIS Spectrophotometer:
1. If uv spectrophotometer cannot be initialized, turn it off and restart it.
2. If the absorption value of the UV spectrophotometer is abnormal, check in turn: whether the wavelength setting is correct (re-adjust the wavelength and re-zero), whether the zero is adjusted during measurement (if it is operated by mistake, re-zero), whether the cuvette is used incorrectly (When measuring the ultraviolet band, use a quartz cuvette) and whether the sample preparation is wrong (if it is wrong, prepare the sample again).