1. Atomic Absorption Spectroscopy (AAS)I
Mentor :
Prof. Kuniyuki KITAGAWA
Assistant:
Dr. Eng.Nelfa Desmira

2. Visible and Ultraviolet Light

3. Uv-Vis Spectrometer Double Beam
Diffraction Grating
Mirror 3
Mirror 2
Half Mirror
Mirror 4
Reference
Cuvette
Sample
Filter
Mirror 1
Light Source Vis (Tungsten)
Light Source UV (Deuterium/D2)
Slit 1
Slit 2
Lens 1
Lens 2
Detector-1
Detector-2
Reference Beam
Sample Beam 1a 1b 2 3 4 6a 6b 7b 7a 5 I0 I

4. Uv-Vis Spectrometer Double Beam
No 1a and 1 b
The UV-Visible spectrophotometer uses two light sources, a deuterium (D2) lamp for ultraviolet light and a tungsten (W) lamp for visible light. Two light sources hit Mirror 1 one pass through slit 1 go to diffraction grating (no.2)
No 2
The grating is able to rotated so a specific wavelength is selectable. From diffraction grating goes to slit 2 and filter (No. 3)
No 3
A filter is used to remove unwanted higher orders of diffraction.
No 4
The light beam hits a second mirror
No 5
splited by a half mirror to 6a and 6b
No 6a and 6b
Half of the light is reflected (6a), the other half passes through (6b)
No 7a
One of the beams is allowed to pass through a reference cuvette.
No 7b
the other passes through the sample cuvette. The intensities of the light beams are then measured at the end

5. Beer-Lambert Law
The Beer-Lambert law is the linear relationship between absorbance and concentration of an absorbing species.
Experimental measurements are usually made in terms of transmittance (T), which is defined as: T = I / Io where I is the light intensity after it passes through the sample and Io is the initial light intensity.
The relation between A and T is: A = -log T = - log (I / Io)
where A is the measured absorbance

6. Transmittance
The relationship between absorbance and transmittance is illustrated in the following diagram:

7. Assignment Calculate the transmission for absorbance A 0.6 and 0.06
How to make correction for background absorption caused by sample matrices   using a one-beam spectrophotometer?
Explain the system of single beam Uv-Vis Spectrometer

8. Atomic Absorption Spectroscopy (AAS) II
Mentor :
Prof. Kuniyuki Kitagawa
Assistant :
Dr. Eng. Nelfa Desmira

9. Atomic Spectroscopy
A method to analyze the elemental composition using atomic absorption or emission
Energy transition electrons of atoms
Absorption
Emission E1 E1 v1 1 1 2 3
Excited State
Excited State E2 E2 v2 2 E3 E3 v3 3 
Ground State E0
Ground State Ej
h = Ei– E0
i = 1.2 and 3
h = Ej – Ei
i = 1.2 and 3

10. Atomic Absorption SpectroscopyEj
Beer Lambert Law : I0 I E0
Where :
A = absorbance/Emission
T = Transmitance
Atomic Absorption Spectroscopy :
The term used when the radiation absorbed by atoms is measured
E0 and Ej : energy levels where Ej higher than E0.
Arrow line: Absorption

11. Atomic Absorption Spectrometry
Detector
Output
Atomized Sample
(Flame)
Lens
Radiation Source
Monochromator
Flame Atomic Absorption Spectrometry
AAS consist of two type: Flame AAS and Graphite-furnace AAS.
Please open this link :

12. Atomic Absorption Spectrometry
Radiation Source
Hollow-Cathode Lamp
Atomization Sample
AAS analyzes atoms in gas phase so atoms in a sample must heated/vaporized in a high-temperature source such as a flame or graphite furnace. Flame AA is suitable to analyze solutions, while graphite furnace AA is able to analyze solutions, slurries, or solid samples.

13. Atomic Absorption Spectrometry
Monochromator and Detector
AA spectrometers use monochromators and detectors for UV and visible light.
Monochromator is used to isolate the absorption line from background light due to interferences.

14. Assignment
Explain the detail of flame atomization absorption spectrometry (FAAS)
Explain the detail of graphite furnace atomization absorption spectrometry (GAAS)
Compare the detection limits of FAAS and GAAS and mention their applications respectively