Dirty-water approach

Equations 3-5 and 3-6 apply only to dilute solutions (< 0.02 M). In extremely dilute solutions, the denominator in Equation 3-6 approaches unity, and this equation reduces to its simplest possible form, 3-7, referred to as the Debye-Hiickel Limiting Law. The limiting law is truly limiting and not a very useful law, however. Some chemists say it is only useful in "slightly dirty water". 

Frost, N., P. GriflBths, and R. Fanelli. 2008. Peering into dirty waters the potential and implications of a new approach to monitoring drug consumption. Addiction 103 1239 1241. 

Although most of the particulate in the off-gas from the furnace can be captured by the electrostatic precipitators before condensing the phosphoms, some carryover into the product is inevitable. This particulate is partly separated into the condenser water. The remainder reports to the phosphoms to yield either dirty product or a stable emulsion called phosphoms mud or sludge. Over many years a variety of approaches have been used to minimize the formation of sludge and to recover phosphoms product from the sludge. 

SPME can be used to extract semivolatile organics from environmental waters and biological matrices as long as the sample is relatively clean. Extraction of semivolatile organic compounds by SPME from dirty matrices is more difficult [134], One strategy for analyzing semivolatiles from dirty matrices is to heat the sample to drive the compound into the sample head-space for SPME sampling another approach is to rinse the fiber to remove nonvolatile compounds before analysis [134],... 

The first and most obvious approach is to use a water quench. This does not permit any of the sensible heat to be recovered and results in a substantial "dirty" waste water stream which must be treated. The other approach, which was finally adopted, was to use a recycle gas quench (about 4 to 1) which cooled the reactor gas to 700°C. Following this, the total gas stream was passed through a series of Transfer Line (heat) Exchangers (TLE). 

Probably the best general description of a comet ever made was by the American astronomer and comet authority Fred Whipple (1906-2004). Whipple called comets "dirty snowballs." That term is apt because cometary nuclei consist primarily of ices of water, ammonia, carbon dioxide, and methane mixed with dust particles. A comet that is distant from the Sun is essentially invisible because its nucleus is so small and dark. As the comet approaches the Sun, however, solar radiation vaporizes some of the ices that make up the nucleus. The gases thus released, along with some of the dust in the nucleus, form the familiar and spectacular features of a comet. 

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