The University of Minnesota Biocatalysis/Biodegradation Database (UM/BBD) contains "microbial biocatalytic reactions and biodegradation pathways primarily for xenobiotic, chemical compounds." A new microbial...

A=B, by Petkovsek, Wilf, Zeilberger, is a book about identities, especially identities involving binomial sums and hypergeometric identities, and ways to prove them using computer programs. The entire text may be...

The Department of Computational Quantum Chemistry at the University of Georgia makes available the Website, A Brief Review of Elementary Quantum Chemistry, designed by David Sherrill. The discussed topics are organized...

This is an animation of a comparator with noisy input voltage. The device compares the voltages and switches to the larger one. Voltages and parts of the circuit of this 3-D animated gif are highlighted with different...

The Physics Laboratory of the National Institute of Standards and Technology (NIST) provides A Walk Through Time, a site devoted to examining the question of how humans have measured time throughout history. In one...