Pure NMR vs Math Keeper+

Pure NMIdentify NMR impurities instantly with Pure NMR. Pure NMR is the essential reference tool for chemists working with NMR spectroscopy. Quickly identify unknown peaks in your ¹H and ¹³C spectra by searching a comprehensive database of common laboratory impurities and residual solvents. FAST & ACCURATE SEARCHES Enter a chemical shift value and instantly find all matching impurities within your specified tolerance range. Search across multiple deuterated solvents including CDCl₃, DMSO-d₆, CD₃CN, D₂O, and more. COMPREHENSIVE DATABASE Access chemical shift data for over 60 common impurities including: Residual solvents (water, acetone, ethyl acetate, etc.) Common reagents (triethylamine, acetic acid, TMS, etc.) Laboratory contaminants (silicone grease, pump oil, etc.) Stabilizers and additives (BHT, BHA, etc.) All data is based on peer-reviewed literature (Fulmer et al., Organometallics 2010; Gottlieb et al., J. Org. Chem. 1997). KEY FEATURES - Search by chemical shift (1-H or 13-C) - Adjustable tolerance range (0.0 to +/-1.0 ppm) - Support for 14 deuterated solvents - View complete assignment information (multiplicity, coupling constants) - Add your own custom impurities to the database - Browse all impurities by solvent - Dark mode support - Customizable interface colors - No internet connection required - fully offline PERFECT FOR Organic chemists characterizing compounds Graduate students learning NMR spectroscopy Research scientists in academia and industry Anyone who needs quick impurity identification SCIENTIFICALLY VALIDATED All chemical shift values are sourced from authoritative scientific publications, ensuring accuracy and reliability for your research. EASY TO USE Select your nucleus (1-H or 13-C) Choose your deuterated solvent Enter the unknown chemical shift Get instant results with full spectroscopic details Stop flipping through reference books or searching online databases. Pure NMR puts all the essential impurity data right at your fingertips. PRIVACY FOCUSED Pure NMR works completely offline. No data collection, no tracking, no internet required. Your searches stay on your device.You can also custom save the Default conditions so that every time the App starts up, you are ready to go without having to select them again.

Math Keeper is a handy reference app for anyone who would like a refreshment of their memory about high school math, or perhaps anyone who would like a refreshment of their memory about what they were supposed to have learned in class yesterday. If you identify with either, you have come to the right place. The app includes over 100 math formulas for a quick jog of the memory, and you are able to edit them, write notes, and add your own if you so desire. A calculator is also built in for convenience, just one swipe away. Good luck.