Word Finder - evaporation

definition

The process of a liquid converting to the gaseous state.

definition

The process in which all or a portion of liquid (in a container) is turned into vapour, in order to increase the concentration of solid matter in the mixture.

definition

That which is evaporated; vapor.

There was evaporation of water from the leaf.

The annual evaporation from water surfaces is from 60 to 150 in.

The test tube is tightly corked to prevent evaporation, and allowed to stand for some hours.

The space between the parts of such substances is too large to admit of capillary action; hence the water conveyed to the surface of the soil is prevented from passing upwards any further except by slow evaporation through the mulching layer.

The solution on evaporation deposits a hydrated form, H 2 SiF 6.2H 2 O, which decomposes when heated.

The sugar thus produced, by constant stirring and evaporation almost to dryness, forms a species of small-grained concrete.

An economical method of evaporation must be found.

Cadmium sulphate, CdSO 4, is known in several hydrated forms; being deposited, on spontaneous evaporation of a concentrated aqueous solution, in the form of large monosymmetric crystals of composition 3CdSO 4.8H 2 O, whilst a boiling saturated solution, to which concentrated sulphuric acid has been added, deposits crystals of composition CdSO 4 4H 2 0.

In endeavouring to make a pan of less power do as much and as good work as one of greater power, they have imagined many ingenious mechanical contrivances, such as currents produced mechanically to promote evaporation and crystallization, feeding the pan from many points in order to spread the feed equally throughout the mass of sugar being cooked, and so on.

Some crystallizers are made entirely cylindrical, and are connected to the condenser of the vacuum pan; in order to maintain a partial vacuum in them, some are fitted with cold-water pipes to cool them and with steam pipes to heat them, and some are left open to the atmosphere at the top. But the efficiency of all depends on the process of almost imperceptible yet continuous evaporation and the methodical addition of syrup, and not on the idiosyncrasies of the experts who manage them; and there is no doubt that in large commercial processes of manufacture the simpler the apparatus used for obtaining a desired result, and the more easily it is understood, the better it will be for the manufacturer.

Evaporation of the water and anything that lowers the hydrogen-ion concentration have the same effect.

The processes of evaporation and concentration are carried on as they are in a cane sugar factory, but with this advantage, that the beet solutions are freer from gum and glucose than those obtained from sugar-canes, and are therefore easier to cook.

Evaporation and subsequent distillation under a high vacuum gives crude glycerin.

Evaporation of the Juice to Syrup. - The third operation is the concentration of the approximately pure, but thin and watery, juice to syrup point, by driving off a portion of the water in vapour through some system of heating and evaporation.

The use of multiple-effect evaporation made it possible to raise the steam for all the work required to be done in a well-equipped factory, making crystals, under skilful management, by means of the bagasse alone proceeding from the.

It is only known in solution; evaporation of the solution yields the pentoxide.

The excess of heat received in equatorial regions expands the water, but at the same time excess of evaporation concentrates it, so that the density increases.

We can calculate the heat of formation from its ions for any substance dissolved in a given liquid, from a knowledge of the temperature coefficient of ionization, by means of an application of the well-known thermodynamical process, which also gives the latent heat of evaporation of a liquid when the temperature coefficient of its vapour pressure is known.

In the best days of the so-called Jamaica Trains in Demerara, three-quarters of a ton of coal in addition to the megass was burned per ton of sugar made, and with this for many years planters were content, because they pointed to the fact that in the central factories, then working in Martinique and Guadeloupe, with charcoal filters and triple-effect evaporation, 750 kilos of coal in addition to the megass were consumed to make woo kilos of sugar.

The defecated cane juice, having lost about 70% of its bulk by evaporation in the multipleeffect evaporator, is now syrup, and ready to enter the vacuum pan for further concentration and crystallizaHoward's tion.

If it be rubbed in or evaporation be prevented, it acts, like alcohol and chloroform, as an irritant.

The process of natural evaporation in the salines or salt gardens of the margin of warm seas made the composition of sea-salt familiar at a very early time, and.

Shallow planting, whether of wall trees or standards, is generally to be preferred, a covering of a few inches of soil being sufficient for the roots, but a surface of at least equal size to, the surface of the hole should be covered with dung or litter so as to restrain evaporation and preserve moisture.

The one is probably derived from the other, most rock salt deposits bearing evidence of having been formed by the evaporation of lakes or seas.

With open pans the vapour is free to diffuse itself into the atmosphere, and the evaporation is perhaps more rapid.

In Britain the brine is so pure that, keeping a small stream of it running into the pan to replace the losses by evaporation and the removal of the salt, it is only necessary occasionally (not often) to reject the mother-liquor when at last it becomes too impure with magnesium chloride; but in some works the mother-liquor not only contains more of this impurity but becomes quite brown from organic matter on concentration, and totally unfit for further service after yielding but two or three crops of salt crystals.

Sometimes, to get rid of these impurities, the brine is treated in a large tub-`(bessoir) with lime; on settling it becomes clear and colourless, but the dissolved lime forms a skin on its surface in the pan, retards the evaporation and impedes the crystallization.

Some of the saline springs yield salt enough to render their evaporation profitable.

This is, of course, due to the excess of evaporation over the amount of water supplied by its two feeders, the Amu-darya and the Syrdarya, both of which are seriously drawn upon for irrigation in all the oases they flow through.

Thallic chloride, T1C1 3, is obtained by treating the monochloride with chlorine under water; evaporation in a vacuum gives colourless deliquescent crystals of T1C1,.H20.

Thallic sulphate, T1 2 (SO 4) 3.7H 2 O, and thallic nitrate, Tl(NO 3) 3.8H 2 0, are obtained as colourless crystals on the evaporation of a solution of the oxide in the corresponding acid.

Red ochre, for which there is only a limited market, is mined on Ormuz, Abu Musa and other islands in the Gulf; salt, as deposits, on Ormuz and Qishm I., and by evaporation, near Mohammerah, Fao and elsewhere on both sides of the Gulf; gypsum is widely distributed throughout the Gulf; iron, as haematite and pyrites, widely found through the Ormuz series.

At the Kohat mines, and in the salt evaporation works on the sea-coast, with the exception of a few of the Madras factories, the government does not come between the manufacturer and the merchant, except in so far as is necessary in order to levy the duty from the salt as it issues from the factory.

The immediate cause of collapse seems to have been cold, due to the deficiency of oil fuel in the Mount Hooper depot, the reason for which was stated to be evaporation through defective stoppers.

The least trace of damp in the lagging, or of moisture condensed on the surface of the calorimeter, may produce serious loss of heat by evaporation.

Evaporation of a solution at ordinary temperatures gives colourless monoclinic prisms of Th(SO 4) 2.9H 2 O, which is isomorphous with uranium sulphate, U(S04)2.9H20.

Another method, which is suitable for volatile liquids or low temperatures, is to allow the liquid to evaporate in a calorimeter, and to measure the quantity of heat required for the evaporation of the liquid at the temperature of the calorimeter and at saturation-pressure.

The second method may be called the method of evaporation.

Bunsen and Kirchhoff (Ann., 1860, 113, p. 337), in the spectroscopic examination of the residues obtained on evaporation of water from a mineral spring at Diirkheim, being characterized by two distinctive red lines.

Another peculiar and very general feature of the drainage system of the state is the presence of numerous so-called river " sinks," where the waters disappear, either directly by evaporation or (as in Death Valley) after flowing for a time beneath the surface.

In wet seasons it overflows its banks and becomes greatly extended in area, discharging its surplus waters into the San Joaquin; but in dry seasons the evaporation is so great that there is no such discharge.

And finally, in the fourth place, except on the coast the disagreeableness of the heat of summer is greatly lessened by the dryness of the air and the consequent rapidity of evaporation.

On boiling gelatinous silica with ammonium polytungstate and evaporating with the occasional addition of ammonia, ammonium silicodecitungstate is obtained as short rhombic prisms. On adding silver nitrate and decomposing the precipitated silver salt with hydrochloric acid, a solution is obtained which on evaporation in a vacuum gives the free acid as a glassy mass.

In the central and southern portions of the plateau the streams either flow into salt lakes, where their waters pass off by evaporation, or into freshwater lakes, which have no visible outlets.

The great evaporation going on from the surface probably causes a slow vertical circulation in the depth, the salter colder waters sinking, and ultimately escaping to the Indian Ocean.

The wines which remain for a long period in cask gradually lose alcohol and water by evaporation, and therefore become in time extremely concentrated as regards the solid and relatively non-volatile matters contained in them.

As a rule, wines which are kept for many years in cask become very dry, and the loss of alcohol by evaporation - particularly in the case of light wines - has as a result the production of acidity by oxidation.

The sun is sufficiently powerful to cause the evaporation of the water in the grape through the skin without any preliminary loosening of the latter by the action of the botrytis cinerea or any other micro-organism.

In the lowlands it loses much of its volume through evaporation and absorption by the sands, and through irrigation, and in its lower course in New Mexico its bed is frequently dry.

In the valleys there are many small streams whose waters never reach the ocean, but disappear by seepage or evaporation.