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Practical Applications of Infrared Microspectroscopy for Industrial Problem Solving. Sample Preparation: Garbage In … You Know the Rest P.T. McKittrick, Ph.D. Nalco Company. Instruments Provide Data, Not Answers!. 90. 88. 86. 799.1. 84. 627.2. 535.6. 82. 1260.0. 1452.0.
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Practical Applications of Infrared Microspectroscopy for Industrial Problem Solving Sample Preparation: Garbage In …You Know the Rest P.T. McKittrick, Ph.D. Nalco Company
Instruments Provide Data, Not Answers! 90 88 86 799.1 84 627.2 535.6 82 1260.0 1452.0 1377.1 80 %T 1523.8 78 76 2928.8 74 1652.2 72 3329.2 70 1034.6 68 4000 3500 3000 2500 2000 1500 1000 500 Wavenumbers (cm-1)
http://www.jwst.nasa.gov/images/em_spectrum_satellite.jpg http://upload.wikimedia.org/wikipedia/en/6/6f/IR_summary_version_2.gif
A. OH stretch B. Aromatic CH stretch C. Methylene CH Stretch D. Overtones E. CC ring stretch F. OH bend G. CO stretch H. OOP CH bend
Infrared Micro-what? • Two names in use in the literature • Infrared Microscopy • Infrared Microspectroscopy • Same thing • Microscope with optics for the infrared coupled to an FTIR for obtaining spectra
The Three Functions of a Microscope • Focus the radiation onto the sample • Collect the transmitted or reflected energy and image the energy onto a detector • Provide the user a means of observing the sample
FTIR coupled to a Light Microscope The first union of an FT-IR with a microscope. Image courtesy of G. Shearer, The McCrone Group
Four Things to Keep in Mind • Morphology is important. The sample is part of the optical system. • In general, the path length should be less than 10 microns.
Four Things to Keep in Mind • Morphology is important. The sample is part of the optical system. • In general, the path length should be less than 10 microns. • Generally, transmission is preferable to reflection.
60 Washer Black Residue Micro 40 %T 20 0 Washer Control CH2Cl2 Micro 100 99 %R 98 97 Washer Black Residue Micro CH2Cl2 90 %R 80 Washer Black Residue Micro CH2Cl2 60 50 %R 40 4000 3000 2000 1000 Wavenumbers (cm-1)
Where Did The Fibers Come From? 90 Armor All Wipes 80 %T 70 60 Finished Paper Micro 80 60 %T 40 20 Finished Paper Fuorescent Fibers 80 60 %T 40 20 3500 3000 2500 2000 1500 1000 Wavenumbers (cm-1)
Four Things to Keep in Mind • Morphology is important. The sample is part of the optical system. • In general, the path length should be less than 10 microns. • Generally, transmission is preferable to reflection. • Everything is inhomogeneous
Patricia L. Lang, J.E. Katon and Anthony S. Bonano, Applied Spectroscopy, Vol. 42, # 2, 313-317, 1988
The Latest Developments • First mapping, now imaging • Mapping – moving the sample relative to the detector • Imaging – Linear and focal plane array detectors • Chemometrics • Analysis of large numbers of spectra using data reduction techniques • Better use of optical microscopy • Simpler ways of doing micro-samples • Combined IR and Raman Instruments
Thanks to… • Kate Martin and The ACCA – for inviting me to speak • Nalco – for allowing me to speak • Kirk Ashline – for allowing me to speak with him • All of you – for listening