Liquid collapsible cuvettes

Single- and multi-pass flask are used for qualitative and quantitative spectral analysis of gas mixtures. The use of multi-pass flask makes it possible to confidently detect extremely small concentrations of the components of the gas under study (less than ppm units). • Three types of flask are supplied: 1. single-pass, having a stroke length of 100 mm, with a glass body and windows made of ZnSe, KBr, NaCl 2. multi-pass, with a beam stroke length of up to several tens of meters 3. multi-pass, with a beam stroke length of up to several tens of meters, equipped with a heating system of the working chamber up to 200 ° C and a thermal controller Multi-pass cuvettes have a transparent working chamber made of quartz glass; mirrors with a gold (99.999) coating provide a reflection coefficient in the IR region of at least 98%; additionally, cuvettes can be equipped with pressure and temperature sensors, fittings for controlling gas flow, etc.

A liquid flask with an adjustable layer thickness of the liquid under study is made in the form of an optical-mechanical attachment installed in the cuvette compartment of the FT-801 spectrometer. It contains focusing optics, removable holders of two windows-substrates with a diameter of 10 mm and two adjusting screws placed on the upper panel of the console housing and designed to set the required gap between the windows. A liquid of any degree of viscosity is pre-applied in the form of a small drop to the lower window and then, in the process of smooth convergence of the windows, evenly fills the gap between them. By rotating the adjusting screws and observing the transmission spectrum online, the user has the opportunity to set the desired thickness of the liquid layer, guided by the overall intensity of the entire spectrum or by the intensity of specific absorption bands. In the presence of calibration, which is easy to create using the ZaIR 3.5 program for several samples with a known concentration, the cuvette allows quantitative measurements. The flask is indispensable in the analysis of mixtures containing impurities in small proportions. Technical specifications Transmission in the operating range of the spectrum, % of the input signal at least 50 The recommended number of scans when registering spectra is 16 Time of spectrum registration at 16 scans (resolution 4 cm-1), sec 20 Minimum volume of the studied liquid, mm3 1 The diameter of the focus spot, mm 3 Overall dimensions, mm 200×90×160 Weight, kg 1,1 The figure shows several spectra of the viscous lubricant "Buxol", illustrating the process of selecting the thickness of the sample layer between the windows. The measurement process has a high expressiveness and reproducibility, inexpensive replaceable substrate windows are used, the system is easy to configure and clean, a very small amount of sample is required to obtain high-quality spectra.