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What does SAS Profile say

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j_    a if-u ti

Intensity

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Fg. a) arid b): Lucjan Pijak, ‘Nanostruktora wybrarg*h...” 1998

How SAS can see fractals?

sin ąr qr

Measrred intensityof SAS. can be approximated by: a

dr

o<Ap|r^(r)

0

, włicrc:

o    diameler of a particie (e.g. mi agclomerale)

Ap - iii ffconcc in cl cc Iron tlen siły of a materiał (eąy. SiC) and iis sunoiHiding <e.g. vacmun>

g(r) • correlatlon 1'unctlon of the scatterlnp particie

Norice:    sińce scali cii nę inlcnsily ilq»nds on difference ofccclrcn

densities. the scatcerers can b? both: particles i.e.p. SIC eraiusj or pores. SAS experiment itself carit detennme lypc of llic S-Mllcrcr.

Then. the correlatioti tunctiou we can express as:

g(r)°c f(r)p(r)

, where:

fir) - shuj>e fundion i:l*ilic agglnmcmlc (ilnc>n'l ma ller herc)

>'(r) - denslty of the agglomerate

Aggloincralcsgrown as fniclal slruclurcs havo Ihccondalion

tunction:

g(r)<x f(r)r^v"~³

kiiiI llicy scaller likc:

l(q) « q ^u”

tor 1/A < q < I/a. wt.ere:

A diameter of aeglomecate a    - diamelcr oL pa mary particie

Jt means: we can determfue mass fractal dimensfon L>_m ol agglnmcralc hv .slmplc imusurcmcnl of slopc of.se a lic ring curvc.