Dear sir,
Academics : I graduated a Master in computer science and mechanical engineering from the top French Engineering school and this can be publicly verified.
Ppm is a mass ratio.
Take the volumic mass Mv of magnetite, multiply it by the average volume of a particule (volume = 4/3 Pi . R^3).
This is your particle mass. Multiply it per a million and divide by the voluminous mass of your liquid to know how much liquid you need to add for dilution.
That’s all !
A1 : Volumic Mass Magnetite
A2 : Diameter of a particle
A3 : Volumic mass of water
A4 : 1 000 000 (for a part in a million)
A5 : Volume of water to add for 1 particle
A5 = A1*(4/3*PI()*(D/2)^3)*A4/A3
I’m very very specialized in excel formulas and teaching. I have made hard exercises for people that need advanced understanding of :
- Complex multi-condition Index/match formulas
- Formulas in pivot tables, in number formats, in graph axis colors, in conditional formatting, and in dropdown menus.
- Array-like formulas, that are equivalent to VBA loops. Like “sum of squares of values in a range”, or “min in column A for values when the text in column B is present in text column C”.
- Size reduction for big data files
- Time reduction for files with too many calculations
I know VBA, Java, C++, Python, JavaScript. In 2008 I was already working on a program of 70 000 lines of code in C++ that calculated the braking distance of A320 airplanes.