# rksh

Get flash to fully experience Pearltrees
cool stuff

Help

## the free encyclopedia

In mathematics , and in particular combinatorics , the necklace splitting problem arises in a variety of contexts including exact division ; its picturesque name is due to mathematicians Noga Alon [ 1 ] and Douglas B. West . [ 2 ] Suppose a necklace , open at the clasp, has k · n beads. There are k · a i beads of colour i , where 1 ≤ i ≤ t . Then the necklace splitting problem is to find a partition of the necklace into k parts (not necessarily contiguous), each of which has exactly a i beads of colour i ; such a split is called a k -split.

## Boiling

Boiling is the rapid vaporization of a liquid , which occurs when a liquid is heated to its boiling point , the temperature at which the vapor pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding environmental pressure. [ edit ] Types [ edit ] Nucleate boiling Nucleate boiling of water over a kitchen stove burner Nucleate boiling is characterized by the growth of bubbles or pops on a heated surface, which rise from discrete points on a surface, whose temperature is only slightly above the liquid’s.
Leidenfrost droplet The Leidenfrost effect is a phenomenon in which a liquid, in near contact with a mass significantly hotter than the liquid's boiling point , produces an insulating vapor layer which keeps that liquid from boiling rapidly. This is most commonly seen when cooking ; one sprinkles drops of water in a pan to gauge its temperature—if the pan's temperature is at or above the Leidenfrost point , the water skitters across the metal and takes longer to evaporate than it would in a pan that is above boiling temperature, but below the temperature of the Leidenfrost point. The effect is also responsible for the ability of liquid nitrogen to skitter across floors.

## Leidenfrost effect

In complex analysis , an elliptic function is a meromorphic function that is periodic in two directions. Just as a periodic function of a real variable is defined by its values on an interval, an elliptic function is determined by its values on a fundamental parallelogram , which then repeat in a lattice. Such a doubly periodic function cannot be holomorphic , as it would then be a bounded entire function , and by Liouville's theorem every such function must be constant. In fact, an elliptic function must have at least two poles (counting multiplicity) in a fundamental parallelogram, as it is easy to show using the periodicity that a contour integral around its boundary must vanish, implying that the residues of any simple poles must cancel.