Image Gallery



1) BTEX is the acronym for the mix of organic chemicals that replaced tetraethyl lead in gasolines. The BTEX
fraction is often used as a "marker" for gasoline residues. The infra-red spectra of the major components
are shown above. 

 



2) Glycerol Trioleate is a component found in unsaturated, edible, vegetable oils.


 



3) Glycerol Tristearate is a component found in saturated animal fats.






4) Bio-diesel can be derived from the tri-glycerides of used cooking oils (see IR #2 and #3). Regular Diesel Fuel (see IR #8) is a petroleum derived paraffin fraction while bio-diesel is a mix of long chain saturated and un-saturated fatty acid methyl esters with the typical infra-red spectra shown above.






5) Carbitols are a series of synthetic materials often found as the power transfer fluid in hydraulic braking systems. Water and paraffin hydraulic fluid contamination of the ether-alcohol liquid often leads to brake system failures.






6) Cellophane is the name given to the wood cellulose derived clear plastic sheet used in food packaging. (see Image Gallery #26) The two spectra shown are different materials produced from the same wood pulp digestion process.






7) Glycol coolants are very toxic and have very similar infra-red spectra. Both ethylene and diethylene glycols are used as coolants with the diethylene material also being used as a hydraulic fluid. The presence of these sweet tasting materials in consumer products and foodstuffs have led to many deaths.






8) Diesel fuel traditionally distilled from petroleum is a straight chain paraffin mix centered around the sixteen carbon chain molecule named cetane. The characteristic "saturated" paraffin infra-red spectrum shown can be compared with IR #14






9) Ethylene is a gas, a naturally occurring important plant growth regulator and an artificially manufactured monomer for polyethylene plastics.






10) Polyethylene is the familiar plastic.






11) Kinetic Isotope Effect - Data on the KIE is measured by comparing the rate constants for reactants with different isotopes in key chemical structure positions. The two infra-red spectra displayed show graphically the effect on infra-red stretching frequencies for the hydrogen - deuterium substitution, in tertiary butyl hydroperoxide.
 An unexpected detonation with the potassium salt precursor used to make the heavy atom hydroperoxide put the author in the hospital and subsequently into chemical analysis






12) The table contains data extracted from several well known and reputable literature sources dealing with chemistry, physics and fire investigation.






13) The combustion reactions shown have caused explosions in the authors lab or been the initial source of destruction in fire investigations conducted over the past years. The equations depict the stoicheiometric fuel and oxidizer ratios. Nitrous oxide hydrogen flames are used in atomic absorption spectroscopy and have been encountered in explosion investigations. The second equation is the basis of coal dust explosions, wheat, sugar, and combustible metals will also explode in the airborne dust format. Potassium metal releases sufficient energy to ignite the hydrogen liberated, if water contacts the metal. Aluminum alkyls are pyrophoric with respect to either air or water vapor again releasing sufficient heat energy to ignite the released butane. Hydrocarbons rarely get sufficient oxygen for soot free combustions unless they are initially gases in which case they often cause disastrous explosions before the ensuing fires.


 



14) Triacontane is a 30 carbon long saturated paraffin chain. Saturated paraffins begin with the single carbon methane the chief component of natural gas. (see IG #12) A straight chain paraffin 8 carbons in length is the traditional representative of gasoline and the 16 carbon chain called cetane is typically used as a reference component of diesel fuel (or oil) fractions. The chains longer than the 30 carbon molecule shown above are the constituents of greases and waxes.






15) Familiar Carbonyls - Acetone is most familiar as the solvent that gives nail polish remover its characteristic  
smell while "Banana Oil" is iso-amyl (or pentyl) acetate.






16) Nylon - The familiar plastic is manufactured in several different forms from slightly different starting materials. Polycaprolactam nylon is the infra-red spectrum shown.






17) NMR - Fatty Acid Methyl Esters - Vegetable oils are the usual source of unsaturated fatty acids while saturated acids are often derived from animal fats. Although the positions of the signal peaks remain relatively constant the respective intensity of the signals varies greatly in the nuclear magnetic resonance spectra of the FAME.
Coded assignments demonstrate which hydrogen atoms are causing the signals in these proton NMR spectra. NMR has been used to identify sludge accumulations from leaking bio-diesel fuels. (see Image Gallery #4) 






18) Overspray - Agricultural claims for crop damage from adjacent field overspray have to match with the effects expected from the active ingredient sprayed. Insufficient sunlight, constant cool temperatures or lack of rainfall are all causes for a decrease in crop biomass without plant physiological distortion while frost and plant growth hormone based chemicals, physically distort and destroy plant tissues. The infra-reds displayed are for two common crop spray herbicide active ingredients. 






19) Quantitative IR - Traditionally infra-red spectroscopy is a qualitative technique. The pattern created when an organic compound absorbs radiation between the 2.5 to 16 micron range, is unique for that molecular structure. Quantitative data can be obtained if spectra are collected at several different concentrations of the molecule of interest. (the analyte) The graphic shown was just such a quantitative analysis.






20) Isoprene - In simplified terms rubber can be considered the polymer resulting from the linking together of the isoprene monomer depicted in this infra-red spectrum. Without numerous additives and fillers, the polymer formed is of limited value. Synthetic isoprene has none of the protein found in latex derived materials. 






21) Linseed Oil - Flax seeds contain a highly unsaturated triglyceride oil known as linseed oil. The oil is able to extract oxygen from the air and form a plastic like film. The "drying" ability of the oil has been utilized for hundreds of years as a base resin for paints. The "drying" reaction releases enough heat that it is often, along with other highly unsaturated cooking oils, a source of  "spontaneous ignition". (see I.G. #2) 






22) MDI - Urethanes are a polymeric material formed as shown. The urethane is used as a resin base for adhesives, foamed insulation, paints, sealants and as materials of construction. Urethanes contain the carbamate linkage formed when an isocyanate and an alcohol react. Isocyanates must be handled with care.






23) PET - Bottled water is usually packaged in transparent, recyclable polyethylene terephthalate containers. Fibers and molded transparent food containers are also manufactured from thismaterial. (see P. G. #6) 






24) PVC - Polyvinyl Chloride is a thermoplastic manufactured from the vinyl chloride monomer. The heat moldable polymer is formed into plumbing fittings, that can be cemented together and with suitable additives is a flexible electrical wiring insulator.






25) Polystyrene - White, beaded, foam plastic, hot drink cups are probably the most familiar form of this plastic. Polystyrene is formed into sheets for insulation, form fitting packaging for expensive, mechanically fragile shipments and as a clear thin transparent packaging for food.




 

26) Viscose Rayon and Cellophane - Wood pulp is a source of the raw material used to make the xanthate that can be used to make either "rayon" thread or sheet cellophane. ( see I. G. #6)