Applied Physics

I finally received a Foldscope beta test kit. “Foldscope is an origami-based print-and-fold optical microscope that can be assembled from a flat sheet of paper,” according to the website. The Foldscope “can provide over 2,000X magnification with sub-micron resolution (800nm), weighs less than two nickels (8.8 g), is small enough to fit in a pocket (70 × 20 × 2 mm3), requires no external power, and can survive being dropped from a 3-story building or stepped on by a person.”

The kit came with instructions, perforated cardboard for the microscope assembly parts, lenses, magnetic strips to attach the microscope to a cell phone, and a light module.

Charles Hatchett - Tribologist to the Royal Mint
Excerpt from “The Terrorism Delusion” by Meuller and Stewart:

We have argued that terrorism is a limited problem with limited consequences and that the reaction to it has been excessive, and even delusional. Some degree of effort to deal with the terrorism hazard is, however, certainly appropriate—and is decidedly not delusional. The issue then is a quantitative one: At what point does a reaction to a threat that is real become excessive or even delusional?

Researchers from the U.S. Department of Energy's Lawrence Berkeley National Lab have accelerated subatomic particles to the highest energies ever recorded from a compact accelerator -  a laser-plasma accelerator, which is a new class of particle accelerators that can fit on a table.

The team used a specialized petawatt laser and a charged-particle gas called plasma to get the particles up to speed - electrons in this case - inside a nine-centimeter long tube of plasma. The speed corresponded to an energy of 4.25 giga-electron volts. The acceleration over such a short distance corresponds to an energy gradient 1000 times greater than traditional particle accelerators and marks a world record energy for laser-plasma accelerators.  


Using commercial solar cells, researchers have converted over 40 percent of the sunlight hitting a solar system into electricity, the highest efficiency ever reported.


The diode has a number of applications in electronic circuits. One application you may be familiar with is a rectifier. A rectifier converts alternating current (AC) to direct current (DC). Alternating current periodically changes direction while direct current only flows in one direction. "The most common function of a diode," according to Wikipedia, "is to allow an electric current to pass in one direction (called the diode's forward direction), while blocking current in the opposite direction (the reverse direction)." It’s easy to demonstrate how the diode will let current flow in one direction but block the flow of current in the opposite direction.

Parts needed:

Imagine a car that can't get dirty or a business in Ferguson, Missouri that can't be graffiti'ed by unhinged protesters.

It might be possible with a new class of highly fluorinated super-repellent polymer called a “fluoropore”, which mimics the natural ability of lotus plants and cabbage leaves to make water droplets simply roll away - but for oils too. This lotus effect has been used for producing rough surfaces with special chemical properties. “However, this trick does not work for oils – the lotus plant repels water, but no oil,” says Dr.-Ing. Bastian Rapp of the KIT Institute of Microstructure Technology. “Oil-repellent surfaces need to have another chemical structure, fluoropolymers, for this purpose.” 

How is this for the ultimate miniaturization of energy storage: A new tiny nanopore includes all the components of a battery though it is just is a tiny hole in a ceramic sheet that holds an electrolyte to carry the electrical charge between nanotube electrodes at either end - and 1,000,000,000 can fit in the size of a postage stamp. 

The existing device is a test but the nano-sized battery performs well - and it can be fully charged in 12 minutes, thousands of times.  


The van der Waals force, named after Dutch chemist Johannes Diderik van der Waals, is the total forces between molecules not due due to covalent bonds. The famous sticking power of the geckos is thanks to the van der Waals force. 

Although it was discovered in the 19th century, it is still difficult to quantify when predicting the behavior of solids, liquids, and molecules because precise measurements were only possible for single atoms. That won't do for understanding biomolecules and proteins. They are also responsible for the functioning of certain adhesives and are the reason why geckos can adhere so amazingly well to surfaces, even allowing them to climb smooth walls. 


Physicists have developed a new cooling technique for mechanical quantum systems by using an ultracold atomic gas, cooling a membrane down to less than 1 degree above absolute zero.

Ultracold atomic gases are among the coldest objects in existence. Laser beams can be used to trap atoms inside a vacuum chamber and slow down their motion to a crawl, reaching temperatures of less than 1 millionth of a degree above absolute zero - the temperature at which all motion stops.

At such low temperatures, atoms obey the laws of quantum physics: they move around like small wave packets and can be in a superposition of being in several places at once. These features are harnessed in technologies such as atomic clocks and other precision measurement devices.