We developed an improved particlemeasurement spectroscopic technique, real-time laser transmission spectroscopy (RTLTS), to detect the number-weighted distribution of particles in real time. The measurement system used a deuterium-tungsten lamp for the light source and a spectrometer as the detector. The operating wavelength range was 300-810 nm. To obtain a physically reasonable number concentration from the experimental results, a sequential regularization method was used during the calculations. To verify the feasibility and reliability of RTLTS, the number-weighted distribution of polystyrene particle suspensions was determined over diameters ranging from 0.005 to 2.000 μm in 0.005-μm increments. The measured concentration error was 0.67-32.67%. A mean diameter of the smallest particle we had detected was 0.09 μm, with a 16% oversizing. The measurable concentration range was ~108 #/cc to ~1011 #/cc for 0.895-μmdiameter particles. The measurable concentration range could be adjusted simply by changing the system configuration. This technique is available for both waterborne and airborne particles.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Materials Science(all)