chemia mikroskopowe�dania spoiw0001

Microscopic examin:jtion of binders and sfructure of mortars, concrctcs and ceramic materials

Objeclivc

In tbis labomlmy exercise you will kam to usc optical mieroscopes for examinalion of scUing of cement and gypMim plaster. You will also leant to usc rcikctod-liglu obser^nions for exa]mnc polished surfaec of nuutars, conereies and eeramic rnaierials and assessnient iheirs propeuies.

Baekground

A microscope (Greek: micron = smali and scopos = aim) is an instrument for viewijig objeets Ihai are loo smali to be seen by Lhe tiaked or unaided eye, The science of invcstigating smali objeets using Mich an instrumenl is called microseopy, and lhe term microscopic mcans mi muc or vcry smali. not easily visible willi lhe unaided eye. In olher words, requiring a microscope to examitic.

The most eommon type of microscope (and lhe firsi lo bo invcntcd) is the optical microscope, Tlns is an o pikał instrument containing one or morę lenses Lhal produce an crilarged image ol au objcct placcd i u Lhe focal piane of thu lcns(es).

Componnd optical miemseopes ean magnify an image up LO I000x and are used 10 stiniy thin spęd mens. TypieaUy ihey arc used lo examine a smear. a squash prepa radon, or a thlnly seelioncd slice of some malcriaL Thcre arc ihrcc obicclive Icnscs on a standard compound opdcal microscope,: a seaiming lens (4x), Iow power lens (10x), and high power lens (4()x). Advaneed microseopes olkn have a fourlh objedwe lens. ealJed an oil immersion lens, To usc this len*. a drop of oil is pincet) on top of lhe covcr slip. and lhe lens moved mlo place wlierc it is immersed in lhe oil, An oil ininiersion lens usually has a power of IOQx. The actual power or magnilication is the produa of the powers of tbc eyepiccc (pcular), usually about 10x, and the objcctive lens being used.

Lighl microscopy for materinls analysis generalJy refers lo rctlectod llghl mieroseopy, Ir. 1 his inethod. light is dirccicd vcrtlcally throngh the microscope objective and relluaed back throngh lhe objęci i vc lo an cye piece, view screen or camera. Tran sin i U ed lighl is oecusionally used for 1 ratisparem and iranslucenl malerials.

I igure 1. V1ain paris of transmiucd 1 ijg.be microscope (a) and rctkcied lighl microscope (b). Descriplions for ruirnbers are be Iow.