仪器分析英文课件.ppt

仪器分析英文课件.pptAtomic Mass Spectrometry
Nearly all elements in the periodic table can be determined by mass spectrometry
More selective and sensitive than optical instruments
Simple spectra
Isotope ratios
Much more expensive instrumentation
Still spectroscopy?
What is a mass spectrometer?
Illustration of the ponents of a mass spectrometry system.
Ionization
Source
Mass
Analzyer
Detector
Inlet
all ions
selected
ions
Data
System
Lets talk about mass!
Atomic mass of Carbon
Atomic mass of Chlorine
Atomic mass of Hydrogen
Lets talk about mass!
Atomic mass of Carbon
amu
Atomic mass of Chlorine
amu
Atomic mass of Hydrogen
amu
1amu = 1 dalton (Da)
What about isotopes?
Atomic mass of Carbon
amu for 12C but for 13C
Atomic mass of Chlorine
amu for 35Cl and for 37Cl
Atomic mass of Hydrogen
amu for H and for D!
Just for clarification
Atomic mass
amu, atomic mass units (uma??)
“Da” or Dalton.
kD (kiloDalton for macromolecules)
1 amu = *10-27 kg.
proton, mp = *10-27 kg,
neutron, mn = *10-27 kg.