- TURBIDITY SCIENCE Technical Information Series—Booklet No. 11 By Michael J. Sadar (Hach 1998)
- Definition of turbidity
- Explanation of several measurement methods
- 1.Nash, R. J. & Fisch, M. R. A computer‐controlled turbidity apparatus. Review of Scientific Instruments 60, 3051–3054 (1989).
- I_t = I_0e^{-(α+τ)l}
- We're looking for τ.
- Aparatus for measuring turbidity as function of temperature; includes oven to place sample in. Claims 0.001/mm accuracy and 0.5% precision.
- They measure transmitted light and assume no absorbtion; use a laser of polarized light with beam splitter.
- Use chopper to measure ac instead of dc, claim order of magnitude better long-term stability from it.
- Much improvement from simultaneous reference and measurement beam.
- 1.Development of a Precise and in Situ Turbidity Measurement System | Browse - AIP Conference Proceedings. at <http://proceedings.aip.org/resource/2/apcpcs/914/1/419_1?isAuthorized=no>
- Can't get the article so far.
- 1.Basano, L., Ottonello, P. & Papa, L. LED marine beam transmittance meter. Review of Scientific Instruments 48, 528–530 (1977).
- Comparable to our stuff, but analog.
- 2% accuracy claimed.
- 1.Goring, D. A. I. & Napier, P. G. Light Scattering Determination of the Absolute Turbidity of Water. The Journal of Chemical Physics 22, 147–147 (1954).
- Report of some measurements; low-NTU values needs 90° measurement, not transmission.
- 1.Light Transmittance of Solid Polymeric Film including Spherulites | Browse - AIP Conference Proceedings. at <http://proceedings.aip.org/resource/2/apcpcs/708/1/771_1?isAuthorized=no>
- Not available at this moment.
- 1.Fessenden, R. W. & Stein, R. S. On the Absolute Turbidity of Water. The Journal of Chemical Physics 22, 1778–1779 (1954).
- Another measurement report.
- 1.Hefele, J. R., Lundberg, J. L. & Salovey, R. Simple Ratio Photometer. Review of Scientific Instruments 33, 1256–1258 (1962).
- Analog instrument using photomultipliers and a mercury lamp.
- Taking a reference while measuring (instead of before or after) allows for a less stable light source.
- 1.Krebs, R. P., Perkins, P., Tytell, A. A. & Kersten, H. A Turbidity Comparator. Review of Scientific Instruments 13, 229–232 (1942).
- Article from 1942; old aparatus, old electronics setup; not really useful.
- 1.Wright, W. F. Comparison Type Nephelometer. Review of Scientific Instruments 28, 129–134 (1957).
- Measure transmitted and scattered light with an integrating sphere each, and direct intensity, all three at once.
- Polarized, old style (1952), not really useful.
- 1.Mavromatakis, F. & Franghiadakis, Y. Direct and indirect determination of the Linke turbidity coefficient. Solar Energy 81, 896–903 (2007).
- Not relevant for us; it's about air turbidity.
- 1.Bueche, F., Debye, P. & Cashin, W. M. Expressions for Turbidities. The Journal of Chemical Physics 19, 803–804 (1951).
- Note how to compute turbidity with only tabulated functions. Irrelevant now we have computers.
- 1.Inverted turbidity versus concentration dependence for aqueous polynucleotide–protein mixtures: Visible turbidity at low concentrations | Browse - Journal of Chemical Physics. at <http://jcp.aip.org/resource/1/jcpsa6/v65/i7/p2913_s1?isAuthorized=no>
- Not about measurement method.
- 1.Simple reusable hermetically‐sealed spectrophotometer cuvette for turbidity studies near binary liquid critical points | Rev. Sci. Instrum. - Review of Scientific Instruments. at <http://rsi.aip.org/resource/1/rsinak/v53/i1/p105_s1?isAuthorized=no>
- Cuvettes for measurements that take long (months).
- Probably not relevant for us.