Table 1. Examples of measurements to be used for the various processes, for a range of sample types.

‘NIB’ stands for nothing in beam. This means that there is nothing in the beam path at the sample position; the normal flight-tube exit and entrance windows, for example, are kept in place. ‘Empty cell’ can be replaced with ‘empty capillary’ if capillaries are used. For sooty flames, the non-sooty flame is a best effort, since the burning conditions, and therefore the background, are by definition different.

To determine the scattering of	Process A	Process B	Process C
Solids
Freestanding solid (slab, plate or foil)	NIB	Solid	N/A
Metal alloy	NIB	Alloy	N/A
Nanoparticles embedded in a polymer	NIB	Polymer	Polymer with embedded nanoparticles
Porous membrane in vacuum (dry)	NIB	Membrane	N/A
Only pores in the membrane (dry)	NIB	Non-pore-containing membrane	Dried, porous membrane
Porous membrane in in situ cell (gas/wet)	Empty cell	Filled cell	Immersed membrane
Only pores in the membrane (gas/wet)	Empty cell	Immersed non-pore-containing membrane	Porous membrane
Powders
Powder in between sticky tape (dry)	Sticky tape	Powder in sticky tape	N/A
Powder in in situ cell (gas/wet)	Empty cell	Gas- or water-filled cell	Immersed powder in cell
Liquids
Pure liquids	Empty cell	Liquid	N/A
Nanoparticle dispersion in liquid	Empty cell	Solvent	Solvent + nanoparticles
Proteins in buffer	Empty cell	Buffer	Buffer + protein
Micelles in oil/water dispersion	Empty cell	Oil; water (separately)	Micelles in dispersion
Gases
Pure gases	NIB or empty cell	Gas	N/A
Particles in carrier gas (flow-through cell)	Empty cell	Gas	Gas + particles
Particles in carrier gas (free flowing)	NIB	Gas	Gas + particles
Sooty flames (see note in caption)	NIB or empty cell	Non-sooty flame	Sooty flame