METHOD FOR STUDYING OPTICAL DENSITY OF FLOWING LIQUID Russian patent published in 2021 - IPC G01N21/85 

FIELD: spectrophotometric analysis.

SUBSTANCE: invention can be used to study the optical density of the flowing liquid. The essence of the invention consists in determining the formative parameter β by the difference of the normalized output signals from photodiode lines, which correspond to the intensity maxima of scattered laser radiation passed through a closed cuvette with a reference liquid having a known refractive index n_c, and a flow cuvette with the liquid under study, the refractive index of which must be controlled, the effect of changes in optical density on the error of measuring the refractive index of the current medium is established, in this case, the flow cuvette is located inside a closed cuvette, both cuvettes have a cylindrical shape that ensures maximum contact of the walls, which provides maximum heat exchange for equalizing temperatures, which are controlled by temperature sensors located inside the cuvettes, connected to processing devices, information from these devices enters the processing and control device, a laptop is used for final data processing, in which calibration tables of the refractive index of the reference liquid from the temperature are placed, the closed and flow cuvettes are placed in a vertical position, the laser radiation enters the side face of the cuvette at right angle, a Dove prism is installed in front of the closed cuvette, which changes the direction of half of the laser beam coming out of the collimator, after passing the closed and flowing cuvette, scattered laser radiation enters the dividing prism, the use of which ensures the separation of light fluxes, as a result of which one part of the light flux reduces the signal amplitude of the first photodiode ruler and increases the illumination of the second, the other part of the light flux increases the signal amplitude of the first photodiode line and decreases the signal amplitude of the second photodiode line, measuring their values after processing the signals from the data obtained, using a certain ratio, the value of the change in the optical density of the flowing liquid is determined.

EFFECT: invention provides an increase in the accuracy of determining the change in the optical density of the flowing liquid.

1 cl, 5 dwg