Atomic Absorption Spectrophotometer (AAS) 
                     
                     
                            Atomic absorption units have four basic parts: interchangeable lamps that emit 
                      light at element-specific wavelengths, a sample aspirator, a flame or furnace apparatus 
                      for volatilizing the sample or hydride generation apparatus and a photon detector. In 
                      order to analyze for any given element, a lamp that produces a wavelength of light that 
                      is absorbed by the element is chosen. Subsequently, a sample solution containing the 
                      element is aspirated into the flame. If ions of the element are present in the flame, they 
                      will absorb light produced by the lamp before it reaches the detector. The amount of 
                      light  absorbed  depends  on  the  amount  of  the  element  presents  in  the  sample. 
                      Absorbance values for unknown samples are compared to calibration curves prepared 
                      by running known standard concentrations. 
                            An atomic absorption spectrophotometer (AAS) is a microprocessor controlled double 
                      beam spectrophotometer equipped with a graphite furnace attachment which is employed for 
                      flameless  analyses.  Both  acetylene  and  nitrous  oxide  fuel  mixtures  can  be  used  for  the 
                      analyses of a wide range of elements. 
                                                                  
                                                                   Atomic  absorption  spectrophotometer 
                                                                   provides  accurate  quantitative  analyses 
                                                                   for metals in many samples, e.g. waters, 
                                                                   sediments,    soils,  etc.  Samples  are 
                                                                   analyzed  in  solution  state,  thus  solid 
                                                                   samples  must  be  leached  or  dissolved 
                                                                   using acid solution prior to analyses. 
                                                                    
                                                                  
                                                                  
                                                                  
                                                                  
                     
                               AAS Models                  Atomization method                Location 
                     PE 3100                              Flame                                K315 
                     AAnalyst 200                         Flame                                K315 
                     AAnalyst 200 with FIAS 100           Flame/Hydride                         008 
                     AAnalyst 100 with HG-850             Flame/Graphite Furnace                008 
                     
                     
                    For more information and services, please contact: 
                     
                    Science Officer 
                    Division of Instruments and MUPA 
                    School Of Chemical Sciences, USM, 11800, Penang. 
                     
                    Tel: +60-653 4058   Fax: +60-657 4854   E-mail: MUPA@usm.my