The world’s most intense X-ray laser may soon be the fastest strobe-light camera ever. Two of the laser’s first experiments show the device will be able to take snapshots of single molecules in motion — without destroying them first.

The laser, called the Linac Coherent Light Source, takes up a third of the two-mile-long linear accelerator at the SLAC National Accelerator Lab in Menlo Park, California. In the accelerator hall, tight bunches of electrons wriggle through a series of magnets and give off X-rays billions of times brighter than earlier X-ray sources could muster. The wavelength of these X-rays is comparable to the radius of a hydrogen atom — about one angstrom, or one ten-billionth of a meter — and each pulse can be as short as a few quadrillionths of a second.

Read More http://www.wired.com/wiredscience/2010/06/x-ray-laser/#ixzz0xVjXeTXQ

/od/salt/a/aboutsalt.htm

Salt is the only mineral that people eat; it’s a commonplace substance sought after by animals and humans since the beginning. Salt comes from the sea and from solid layers underground, and that’s all most of us need to know. But if you’re curious, let’s go a bit deeper into the subject.

The Truth About Sea Salt

The sea collects salt, as we all know, but in fact that isn’t really true. In truth, the sea only collects the ingredients of salt. Here’s how that works.

The sea takes in dissolved matter from two sources, rivers that enter it and volcanic activity on the seafloor. The rivers provide mainly ions—unpaired atoms with a lack or an excess of electrons—from the weathering of rocks. The major ions are various silicates, various carbonates, plus the alkali metals sodium, calcium and potassium. The seafloor volcanoes provide mainly hydrogen and chloride ions. All of these mix and match: sea organisms build shells from calcium carbonate and silica, clay minerals take up potassium, the hydrogen is snapped up in lots of different places. After all the electron swapping is done, sodium ion (from rivers) and chloride ion (from volcanoes) are the two survivors.

Read more: http://geology.about.com/od/salt/a/aboutsalt.htm