Curs Bf

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Curs de Biofizică

Prof.dr. Cipriana Ş tefănescu Disciplina de Biofizică

şi Fizică medicală 

10

Vă rugăm: gândiţi!

Fenomene optice sispectre

Fenomene optice sispectre

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Dispersia luminii albe

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Difracţie

Colors seen in a spider web are partiallydue to diffraction, according to someanalyses.[1]

Reflexie

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Refracţie

Reflexie totală

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Relation between different typesof spectra and their principle

electron

level

changes

Gamma ray and X-ray quantum energies are so high

that they cause ionization

 Number 

of available

energy

states

molecular

vibration

 X-ray

scattered 

X-ray

molecular

rotation and

torsion

 X-ray

ionizationionization accompanied

by Compton scattering

ultraviolet

visiblelight

infrared

microwaves

 High,

strongly

absorbed 

Small,

almost

transparent 

 Ionization

energy

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Principiul fizic de producere aspectrelor de emisie şi de absorbţie

 E 2

Spectru de absorb ţie

 E1

  E

Spectru de emisie

  E = h 1

Spectrul luminii albe

(R, O, Y, G, B, I, V)

absenţa  1

 Linie neagră

Fond negru

emisia  1

 Linie în culoarea corespunzătoare frecvenţei 

Spectre de emisie

Spectre du Mercure : Spectre du Néon :

Spectre du Cadmium :

Spectre du sodium :

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Spectre de

absorpţie

Types of spectra related to the energyquantum and the type of structuralphenomenon, at the electromagnetic

radiation interaction with matter

 Phenomenon Region of

 spectrum

Wavelength(nm)

 Nuclear Gamma 0.1 nm

Inner electrons X-rays 0.1 – 1.0 nm

Ionization Ultraviolet (UV) 0 – 200 nm

Peripheral (valence)

electrons

 Near UV and 

visible

200 – 800 nm

Molecular vibrations Near infrared (IR)

and IR 

800 – 2500 nm

Rotation and electron spin

orientation in magnetic

fields

Microwaves 400 mm – 30 cm

 Nuclear spin orientation in

magnetic fields

Radiowaves 100 cm and above

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Spectrulelectromagnetic

Spectrulelectromagnetic

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