Spectral analysis
spectral-analysis

##Intro This is a page to compile, share, and publish research about near-ultraviolet, visible, and near-infrared spectroscopy/spectrometry analysis techniques. Not all will be applicable to our DIY spectrometer, but many are a good starting point for investigation. **If you want to publish research, post it on the Public Lab site and you can add it here too.** If you'd like to try applying some of this research, take a look at the [Spectrometry Activities page](/wiki/spectrometry-activities) and the [Spectrometry Sampling](/wiki/spectrometry-sampling) guide. ##Databases First, let's start with some already available spectral databases, many of which may be **very** difficult to search or use, but which can be used as a basis for identification. Perhaps some could eventually be imported into Spectral Workbench. * http://daihassan.tripod.com/id22.html * http://www.ftirsearch.com/default2.htm (and [usage instructions](/notes/warren/2-18-2013/spectraonlinecom-spectrum-searching)) * NIST database: http://physics.nist.gov/PhysRefData/ASD/lines_form.html (atomic emission spectra) * [HITRAN database](http://hitran.iao.ru/molecule) ([posted by warren](http://publiclaboratory.org/notes/warren/12-10-2010/using-hitran-database-spectral-analysis)) * http://nautilus.fis.uc.pt/st2.5/index-en.html ([posted by b.williams](http://publiclaboratory.org/notes/bwilliams/10-1-2012/specta-reference-libaray)) * ASTER (JPL/NASA) library for remote-sensing (satellite-collected) spectra of surface materials like asphalt or granite: http://speclib.jpl.nasa.gov/ ([online copy here](http://archive.publiclab.org/aster-spectral-library/)) (but mostly in the thermal range, so not very useful for the Public Lab spectrometer) * http://webmineral.com/help/FlameTest.shtml - no line data, just images. But they can be uploaded for comparison -- they are cited to a 1906 publication by Brush & Penfield, so are out of copyright. ##Compiled research Some of the below papers describe other types of spectroscopy such as mid-infrared (MIR) or Fourier-transform infrared (FTIR) and the data they present will not be compatible/comparable with that which we gather in the 400-900nm range. But their methodologies may be a useful reference for those looking to reach similar results in the range our instruments can detect. For each use case below, there might be several approaches to analysis. Read more about different kinds of spectrometry such as fluorescence, absorption, and flame emission spectrometry here: [Spectral Analysis Techniques](/wiki/spectral-analysis-techniques) ###Household products * [Laundry detergent](https://spectralworkbench.org/tag/detergent) (for dyes) * Read over some [published research on how to do this](/notes/joshmc/4-28-2012/setup-uv-testing-specrtrometer) by [JoshMC](/profile/joshmc) ###Metals and soil * Use tag "[soil](https://spectralworkbench.org/tag/soil)" * [Sodium, aluminum, barium and mercury in soil](http://blog.makezine.com/laboratory-54-examine-the-spectrosc/) (Makezine.com) * Method for spectrophotometric determination of amenable cyanide: http://www.epa.gov/osw/hazard/testmethods/sw846/pdfs/9014.pdf * http://www.saimm.co.za/Journal/v083n01p011.pdf - "The most successful of these methods is the variation proposed by Epstein3, which involves the oxidation of cyanide to cyanogen chloride with chloramine-T. The cyanogen chloride is then reacted with pyridine containing pyrazolones, and the blue colour produced is measured at 630 nm. This method is sensitive, and can be used in acid, neutral, or slightly alkaline media." **Atomic emission spectra databases:** * [HITRAN database](http://hitran.iao.ru/molecule) ([posted by warren](http://publiclaboratory.org/notes/warren/12-10-2010/using-hitran-database-spectral-analysis)) * http://nautilus.fis.uc.pt/st2.5/index-en.html ([posted by b.williams](http://publiclaboratory.org/notes/bwilliams/10-1-2012/specta-reference-libaray)) * Oil/coal contamination * laser fluorescence: * http://publiclaboratory.org/notes/warren/7-18-2012/fluorescence-oil-spill-residue-diverse-spectrometer-use * http://publiclaboratory.org/notes/warren/7-26-2012/oil-residue-preparation-spectroscopy * Tag: https://spectralworkbench.org/tag/oilspill ###Beer/brewing * Use tag "[beer](https://spectralworkbench.org/tag/beer)" * http://publiclaboratory.org/notes/warren/8-28-2012/spectral-yeast-tests-mystic-brewery * [Quantifying ethanol content of beer using interpretive near-infrared spectroscopy](http://www.mendeley.com/research/quantifying-ethanol-content-beer-using-interpretive-near-infrared-spectroscopy/) * [Applications of Vibrational Spectroscopy in Brewing](http://onlinelibrary.wiley.com/doi/10.1002/0470027320.s6502/abstract) (may be behind paywall) * [Rapid Determination of Bitterness in Beer Using Fluorescence Spectroscopy and Chemometrics](http://www.skotrat.com/go/default/?LinkServID=5D45FB60-A023-B7AC-6BD7F79FC2F655CE&showMeta=0) ###Wine & grapes * Use tag "[wine](https://spectralworkbench.org/tag/wine)" * http://publiclaboratory.org/notes/warren/1-19-2012/wine-spectroscopy-adam-hasler * [UV-VIS Spectroscopy of Tannins and Phenols in Red Wine](http://www.globalspec.com/reference/6563/UV-VIS-Spectroscopy-of-Tannins-and-Phenols-in-Red-Wine) * [Vintage year determination of bottled Chinese rice wine by VIS-NIR spectroscopy](http://www.ncbi.nlm.nih.gov/pubmed/17995801) * [Near infrared spectroscopy as a rapid tool to measure volatile aroma compounds in Riesling wine: Possibilities and limits](http://era.deedi.qld.gov.au/992/) ###Coffee * Use tag "[coffee](https://spectralworkbench.org/tag/coffee)" * http://publiclaboratory.org/notes/warren/8-29-2012/testing-coffee-spectra-toscaninis * [Discrimination of Arabica and Robusta in Instant Coffee by Fourier Transform Infrared Spectroscopy and Chemometrics](http://www.mendeley.com/research/discrimination-arabica-robusta-instant-coffee-fourier-transform-infrared-spectroscopy-chemometrics-1/) * [Discrimination of organic coffee via Fourier transform infrared-photoacoustic spectroscopy](http://www.mendeley.com/research/discrimination-organic-coffee-via-fourier-transform-infrared-photoacoustic-spectroscopy/) * [Determination of caffeine in decaffeinated coffee by NIR spectroscopy](http://www.camo.com/downloads/resources/application_notes/decaffeinated_coffee_NIR_spectroscopy.pdf) ###Coral/Aquariums/Grow lights * GiulianoM's work on [coral reef lighting](http://www.atlantareefclub.org/forums/showthread.php?s=3ff4c2efe002de643743d2ccbd4d6b49&t=66297&page=5) with custom LEDs * he references [this article on the same topic at AdvancedAquarist](http://www.advancedaquarist.com/2012/3/aafeature?utm_source=nivoslider&utm_medium=slider&utm_campaign=clickthru) * Mediamatic's work on [measuring grow lights](http://mediamatic.net/319662/en/led-growing-light-analyses) in aquaponics ###Agricultural uses * [Spectral analysis of nitrogen levels based on visible-light spectroscopy](http://www.csir.co.za/enews/2012_july/16.html) * Crops, grains, fruits, vegetables, beverages, fats, oils, dairy, eggs, etc etc. [in near-infrared spectroscopy](https://docs.google.com/viewer?a=v&q=cache:nOmy0bzlX8AJ:plantsci.missouri.edu/roberts/NIRmonograph.pdf+&hl=en&gl=us&pid=bl&srcid=ADGEESgSOr3uhxdMsfYxrIchmC9K9H0leBfGOyw8t94Xa_Ft6CU3mDXECwjaICznsEIPBrmpsH-hzONA5cngKDSFUs-SvfWaZqI2xLgs7_aFzcMdqw7DA8KLwUbTaZub3FyhdAWAFQjR&sig=AHIEtbSLVnHpiRhKBKdDxNmBDB2PgWIG9w) * [predicting N, OM, and pH in soil with near-infrared spectroscopy](http://spie.org/documents/Newsroom/Imported/164/2006040164.pdf) (however, uses up to 2500nm) ###DNA/RNA * [DIYBio discussion](https://groups.google.com/forum/?fromgroups=#!topic/diybio/2N5UG7HzRYg) ###Urine ###Astronomy ###Food Contamination Detection * [NIR Spectroscopy for Detection and Quantification of Adulterants in Fresh and Thawed Minced Beef Using Linear and Non-linear Models](http://cigr.ageng2012.org/images/fotosg/tabla_137_C1778.pdf) (detection of pork, fat, offal) * [THE ADVANCEMENT OF SPECTROSCOPIC SENSORS/CHEMOMETRIC ANALYSIS/BIOBASED PRODUCTS FOR QUALITY ASSESSMENT OF FIBER, GRAIN, AND FOOD COMMODITIES](http://www.ars.usda.gov/research/publications/publications.htm?seq_no_115=249599) (detection of soy) * [The development of near infrared (NIR) spectroscopy calibrations for the prediction of wheat and flour quality](http://www.hgca.com/cms_publications.output/2/2/Publications/Final%20project%20reports/The%20development%20of%20near%20infrared%20(NIR)%20spectroscopy%20calibrations%20for%20the%20prediction%20of%20wheat%20and%20flour%20quality.mspx?fn=show&pubcon=345) (detection of wheat gluten?) ...


Author Comment Last activity Moderation
vapecult "Hi Nickha, I am a Vapecult Owner. This is my site Vape juice, vape kit etc. vapecult.co.uk is your main internet vaping source. We are committed to..." | Read more » over 1 year ago
lizimu "nice " | Read more » about 4 years ago
MaggPi "The comment tries to answer questions above but some still need work: this is definitely a relevant parameter to explore, what I'm missing here ..." | Read more » over 4 years ago
amirberAgain "You probably noticed by now that even a thing as simple as RGB2GRAY cand be made in different ways, look for rpi camera debayer to read more on thi..." | Read more » over 4 years ago
amirberAgain "@maggpi, this is definitely a relevant parameter to explore, what I'm missing here are a few equations which describe the relation between the line..." | Read more » over 4 years ago
MaggPi "Thanks! Interesting that 580nm plus or minus x nm could be a type of spectral anchor. I am wondering if an opencv technique could be used to ca..." | Read more » over 4 years ago
cfastie "If you know the spectral sensitivity of each channel in the sensor in the camera you are using, you can adjust the brightness (intensity) at each w..." | Read more » over 4 years ago
Ag8n "Ratio= (absorbance interesting area/absorbance uninteresting area ) " | Read more » almost 5 years ago
Ag8n "Here are some calculations. Don't know if they will help... Btw, I noticed the halogen, and would suggest holding on to it. At least until other t..." | Read more » almost 5 years ago
jkew "I'm specifically looking at tracking carbohydrate metabolism in bacteria. Early on I'll just be using phenol red which is a clear indicator when ac..." | Read more » almost 5 years ago
Ag8n "Excellent data!! What direction are you headed for analysis? Absorbance, transmittance, reflectance, or some of the ratio stuff done with other a..." | Read more » almost 5 years ago
warren "This is so cool! " | Read more » almost 5 years ago
Ag8n "One of the links on the page was for an aotf nir spectrophotometer. Part of this instrument was a vco that could be tuned from 75 mhz to 120 mhz. ..." | Read more » almost 5 years ago
31gane "I am not clear of which instrument you are suggesting about ? i have mentioned my own work (still will write and share more about it, which i hope ..." | Read more » almost 5 years ago
Ag8n "I may be wrong, but it looks like a fast Fourier transform (FFT) version of this instrument is possible. Any suggestions on how to approach that?..." | Read more » almost 5 years ago
hppyromz "We do not disclose your personal information to anyone, except in accordance with the Privacy Act. Authorized disclosures include limited circumsta..." | Read more » over 5 years ago
warren "Hi, can you tell a bit more about the context of your question? Do you have photos of what you suspect is gasoline? " | Read more » over 5 years ago
Matej "Cool! Thanks Jeff! This is helpful. " | Read more » over 6 years ago
warren "What I did to compare is to calibrate on a CFL, then scan a tube fluorescent, so that the methodology for calibration is the same: https://spectra..." | Read more » over 6 years ago
Matej "Interesting. I actually did kind of an "educated guess" calibration but I couldn't find more but one blue peak. I know that in the "usual" CFL ther..." | Read more » over 6 years ago
warren "Actually this looks calibrated, no? " | Read more » over 6 years ago
Matej "@warren: in response to: "Can you try re-calibrating this one, as I think it was calibrated during a brief bug (it shows being calibrated on 1/26/1..." | Read more » over 6 years ago
Matej "@ethanbass for calibration I am not smoothing the spectra. I just thought it could be helpful when comparing them and adding them to a set. " | Read more » over 6 years ago
Matej "Hi Jeff, Thanks for the info about the bug! I Will recalibrate right away. I discussed with Gretchen and I think I will keep using this bulb since ..." | Read more » over 6 years ago