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The method of colorimetric plate inspection for experimental instrument is briefly introduced
author：管理員 Publication time：2016-09-02 10:30:22 Read：
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| 1. Inspection of light transmittance: In a certain wavelength, air as a blank to adjust 100, with the baffle 0, the transmittance of the color plate is greater than 84, if not, please clean the color plate until the transmittance is qualified, otherwise, replace it. 2. For the same colorimetric dish, the difference of transmittance under two different wavelengths is less than 5 3. Pairing check of two colorimetric dishes: Add potassium dichromate standard solution 525nm to the colorimetric dish for its maximum absorption wavelength,2/3 high, wipe clean Put in the light path, take one of them as a blank, adjust 100 and 0, and measure the transmittance of the other one The difference between the two must not be greater than 0.5. Distilled water was measured at 220nm and 700nm in a quartz absorption tank of the same light diameter. The glass absorption tank was filled with 30mg/L potassium dichromatate solution, which was measured at 440nm and distilled water at 700nm. The transmittance ratio of one tank was adjusted to 100, and the transmittance ratio of other tanks was measured. In the practical work, can use the following calibration method: under the measuring wavelength, frosted surface will absorb pool number with a pencil, to clean the absorption pool into the determination of solvent, with one of them as the reference, the determination of the absorbance of other absorption pool, if measuring the absorbance of zero equals the absorbance or two absorption pool, the pool for pairing absorption. If the pair cannot be matched, the absorption pool with the lowest absorbance can be selected as the reference, the absorbance of other absorption pools can be determined, and the correction value can be obtained. When the sample is measured, the solution to be measured is loaded into the calibrated absorption tank, and the measured absorbance value minus the modified value of the absorption tank is the real value of the measurement. We usually measure the wavelength, in each absorption pool into distilled water, one of them as A reference, that is, at the transmittance T to adjust 100, and then to the absorbance of A, then the reference of the absorbance is zero, the determination of the remaining three absorbance. |