Differential refractometer BI-DNDC

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The BI-DNDC is a deflection type refractometer that may be purchased for use in either batch or GPC/SEC mode. In batch mode, the specific refractive index increment, dn/dc, is determined. This value is required as a parameter in molecular weight measurements using light scattering. In GPC/SEC mode, dn/dc is already known, and the instrument is used as a concentration detector for GPC/SEC applications. All major features are user programmable in order to achieve the maximum flexibility. The BI-DNDC can be set using the front panel controls and read using the LED readout or by an external computer. It includes a microprocessor, which allows user-friendly handling of all functions of the instrument, as well as refractive index and temperature data transfer to a personal computer via a standard serial interface. Most importantly, warm-up time for the BI-DNDC is only one hour, much less than other models on the market. Features at a glance Fast instrument warm-up, ~ 1 hour! Sensitivity, 2.5 x 109 ΔRIU Autozero Reference cell flush 9 measurement ranges DNDCW Windows™ software Active temperature control to 80 °C Wavelength selection: 620, 535 or 470 nm Determination of dn/dc The dn/dc determination requires calibration of the batch mode instrument with a solvent/solute combination with known dn/dc, typically KCl in water. The calculated constant is not solvent dependent and may be used for all further measurements. In batch mode, the instrument comes with BI-DNDCW software for use with an external PC. Included with the BI-DNDC instrument is a syringe kit with PEEK™ and Teflon ® tubing, fittings and syringes.