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"Mass Spectrometry by the Numbers, Identifying Small Molecules from Accurate-Mass Fragmentation Data" 15-Nov-2018

Dan Sweeney's new book on mass spectral identification was recently published. This book describes the theory of "partitioning" and how this approach was implemented as a simple Excel Add-In. The book has many examples. This book can now be purchased on the Amazon website: "Mass Spectrometry by the Numbers"

Similar Partition Searching 08-Oct-2017

Rational Numbers Search was moved from our own MathSpec server to Amazon AWS. This increased CPU power now makes in possible to search every MS/MS spectrum in a chromatogram. Contact us now for your free two-week trial. To see exactly how Similar Partition Searching (SPS) works, please view our short MathSpec YouTube Video on SPS.

Similar Partition Searching 4-28-2016

Rational Numbers Search has been moved from our own MathSpec server to Amazon AWS. This increased CPU power has allowed us to also add simultaneous searching for similar compounds.

New Capabilities Added 02-19-2016

Two new worksheets have been added to the Excel Add-In.

The first worksheet is a summary of all of the elemental compositions of all assigned fragments. With built-in filters for each parameter, this makes it much easier to sort through the results that have a large number of possible molecular formulas.

The second worksheet is a high resolution isotope calculator that tabulates the expected masses of the first and second isotopes. The isotopic patterns of the first and second isotopes are then plotted in color in a normal distribution based on the selected resolution setting. (example here)

Excel® 2016 11-25-2015

The Excel Add-In is compatible with Excel 2016. Use the installation video (MathSpec YouTube) for Excel 2013.

SubFragment Color Change 11-9-2015

Based on feedback, the color of the fourth subfragment has been changed to a shade of purple, making it easier to distinguish from the other cells.


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