Day and night (1938). Woodcut in black and grey (two blocks).

Hydrodynamic effects in non-newtonian fluides.

A non-Newtonian fluid is a fluid in which the viscosity changes with the applied strain rate.

This gives rise to several interesting effects. The Barus effect:



The Weissenberg effect:



And my personal favorite, Kaye effect. The video is really well made, and it even demonstrates a steady-state (continuous) version of Kaye effect:

Benzene as a dienofile.

The only known example of benzene acting as a dienofile:"Perspective on Fluorocarbon Chemistry", D.M. Lemal, JOC 2004, 69(1), 1. It's a really good introductory article for anybody interested in fluoroorganic chemistry.

Reptiles, 1943 (lithograph). M. C. Escher.

Andrew's Glacier Cirque, RMNP.

I wonder if there is a route following this ridge line:And another one:

Spotting the fake smile.

Here is a really interesting test by BBC. After you get through all the smiles, it gives some pretty interesting info on distinguishing genuine and fake smiles (with videos).

SF6 (Xe?) and Archimedes.

A pretty cool twist on Archimedes:



I wonder what gas they use, it's too bad they don't say...