In-vacuo sentence example
A solution of the free acid may be obtained by decomposing the barium salt with dilute sulphuric acid and concentrating the solution in vacuo until it attains a density of about 1.35 (approximately), further concentration leading to its decomposition into sulphur dioxide and sulphuric acid.
The solution obtained may be evaporated in vacuo until it attains a density of 1.46 when, if partially saturated with potassium hydroxide and filtered, it yields crystals of potassium pentathionate, K 2 S 5 0 6.3H 2 0.
Others are deprived of a part of their more volatile constituents by spontaneous evaporation, or by distillation, in vacuo or otherwise, at the lowest possible temperature.
It is there shown that every substance, transparent to light, has a definite refractive index, which is the ratio of the velocity of light in vacuo to its velocity in the medium to which the refractive index refers.
To being the wave-length in vacuo.Advertisement
It is unquestionably better and easier to evaporate in vacuo than in an open pan, and with a better system of firing, a more liberal provision of steam generators, and multiple-effect evaporators of improved construction, a far larger yield of sugar is obtained from the juice than was possible of attainment in those days, and the megass often suffices as fuel for the crop.
Since Howard published his invention the vacuum pan has been greatly improved and altered in shape and power, and especially of recent years, and the advantages of concentrating in vacuo having been acknowledged, the system has been adopted in many other industries, and crowds of inventors have turned their attention to the principle.
In certain districts, notably in the Straits Settlements, syrup is prepared as described above for crystallization in a vacuum pan, but instead of being cooked in vacuo it is slowly boiled up in open double-bottom pans.
The wholesale jam manufacturers of the present day use this sugar; they boil the jam in vacuo and secure a product that will last a long time without deteriorating, but it lacks the delicacy and distinctive flavour of fruit preserved by a careful housekeeper, who boils it in an open pan with cane sugar to a less density, though exposed for a short time to a greater heat.
A very small sphere is said then to possess a charge of one electrostatic unit of quantity, when it repels another similar and similarly electrified body with a force of one dyne, the centres being at a distance of one centimetre, provided that the spheres are in vacuo or immersed in some insulator, the dielectric constant of which is' taken as unity.Advertisement
To avoid unnecessary complications we shall assume this latter condition in all the following discussion, which is equivalent simply to assuming that all our electrical measurements are made in air or in vacuo.
The brine is cooled in a tank filled with spiral pipes, in which anhydrous ammonia, previously liquefied by compression, is vaporized in vacuo at the atmospheric temperature by the sensible heat of the returncurrent of brine, whose temperature has been slightly raised in its passage through the circulating tubes.
Stas recommends solution of the iodine in potassium iodide and subsequent precipitation by the addition of a large excess of water, the precipitate being washed, distilled in steam, and dried in vacuo over solid calcium nitrate, and then over solid caustic baryta.
When the reaction is complete the acid is neutralized with soda, and the phenyl methyl pyrazolone extracted with ether and distilled in vacuo.
Lyman more recently has been able to obtain photographs as far down as 1030 A with the help of a concave grating placed in vacuo.Advertisement
Potassium aluminate, K 2 Al 2 0 4, is obtained in solution by dissolving aluminium hydrate in caustic potash; it is also obtained, as crystals containing three molecules of water, by fusing alumina with potash, exhausting with water, and crystallizing the solution in vacuo.
The above methods give a dilute aqueous solution of hydrogen peroxide, which may be concentrated somewhat by evaporation over sulphuric acid in vacuo.
The alcohol is removed by distillation in vacuo, and by further concentration in vacuo a solution may be obtained which evolves 580 volumes of oxygen.
The sulphate, Ce(SO 4) 2.4H 2 O, is formed when the basic sulphate is dissolved in sulphuric acid; or when the dioxide is dissolved in dilute sulphuric acid, and evaporated in vacuo over sulphuric acid.
The aqueous solution can be concentrated in vacuo over sulphuric acid until it contains 40% of chloric acid.Advertisement
Phosphorus tetroxide, P204, was obtained by Thorpe and Tutton by heating the product of the limited combustion of phosphorus in vacuo as a sublimate of transparent, highly lustrous, orthorhombic crystals.
In this way an exact comparison of the weights in vacuo can be computed, but of course the simplest way of arriving at the result would be by the construction of a strong air-tight case which can be completely exhausted of air by an air-pump, and in which the weighing can then be effected in vacuo.
The difficulty about weighing in vacuo is that it is found almost impossible to exhaust the case entirely, or even to maintain a constant degree of exhaustion, by reason of the leakage connected with the weighing operations, and in consequence weighing in vacuo is not much in favour.
By evaporating in vacuo the solution obtained by dissolving iron in hydrochloric acid, there results bluish, monoclinic crystals of FeCl24H20, which deliquesce, turning greenish, on exposure to air, and effloresce in a desiccator.
The difference between the positive and negative figures seems to depend on the presence of the air; for the difference tends to disappear when the experiment is conducted in vacuo.Advertisement
Availing himself of the admirable generalized co-ordinate system of Lagrange, Maxwell showed how to reduce all electric and magnetic phenomena to stresses and motions of a material medium, and, as one preliminary, but excessively severe, test of the truth of his theory, he pointed out that (if the electromagnetic medium be that which is required for the explanation of the phenomena of light) the velocity of light in vacuo should xvii.