John Jacob Abel was an American biochemist. He was born in 1857 at Cleveland, Ohio and died in 1938. He determined the molecular weight of cholesterol and in 1897 isolated the hormone adrenaline from the adrenal gland. In 1892 he discovered carbonic acid in horseurine and associated it with the production of urea. He also pioneered kidneydialysis. Research John Abel
Thomas Graham was a Scottish chemist. He was born in 1805 at Glasgow and died in 1869. Educated at Glasgow and Edinburgh, in 1827 he commenced teaching private mathematical classes in Glasgow, and in 1829 succeeded to the lectureship of chemistry in the Mechanics' Institution. 1830 he was appointed professor of chemistry in the Andersonian University. In 1831 he established the law that gases tend to diffuse inversely as the square root of their specific gravities. He afterwards made a series of investigations into the constitution of ar-seniates, phosphates, and phosphoretted hydrogen, and into the function of water in different salts.
In 1837 he was appointed professor of chemistry at University College, London, , and soon after settling in the metropolis he was appointed assayer to the mint, holding the post at University College until 1855 when he became master of the Mint. Thomas Graham was the first president of the Chemical Society, founded in 1841.
In 1846 he assisted in founding the Cavendish Society, over which be presided. He read the Bakerian lecture in 1849 and in 1854, the subject of both being the diffusion of liquids, which he further treated before the Eoyal Society in 1861. He distinguished the crystalloids and colloids in liquid solutions, and gave to their separation the name of dialysis, In a subsequent paper, Philosophical Transactions, 1866, he applied these discoveries to gases, under the name of atmolysis. The passage of gases through heated metal plates and the occlusion of gases were also ably investigated by him. Research Thomas Graham
Haemofiltration is a temporary treatment for patients in acute (usually temporary) kidney failure. Large volumes of plasma water are filtered out of the bloodstream, to be replaced by a sterile electrolyte solution. This has the effect of removing waste products, regulating the plasma electrolytes and getting rid of excess water. For critically ill patients it is safer than dialysis. Research Haemofiltration
Dialysis is a method of chemical analysis, depending upon the different degrees of diffusibility of substances in liquids. It was discovered by Thomas Graham in 1861. Research Dialysis
Diffusion is the gradual mixing of gases or liquids when brought into direct contact. Thus, in the case of gases, when a jar of oxygen and a jar of hydrogen are connected together by a tube or opening of any kind, they rapidly become mixed; and their mixture does not depend on gravity, but takes place in opposition to that force, as may be shown by placing the jar of hydrogen gas above the other. Oxygen is sixteen times heavier than hydrogen, bulk for bulk, but the heavier gas moves upwards and the lighter downwards, and the process of intermixture, or diffusion, goes on until the two gases are apparently equably distributed throughout the whole space. After that they have no tendency whatever to separate.
Similarly, if two vessels, one containing oxygen and the other hydrogen, be connected by a tube which is stuffed with a plug of porous material, such as plaster of Paris, the gases gradually diffuse one into the other through the porous plug. The two gases, however, do not pass through the porous separator at equal rates, but in inverse proportion to the square roots of the densities of the gases. Thus in the case of two vessels, one containing hydrogen and the other oxygen, which is sixteen times as heavy as hydrogen, the hydrogen will pass towards the oxygen jar four times as quickly as the oxygen will pass towards the hydrogen jar.
Kindred phenomena occur when two liquids that are capable of mixing, such as alcohol and water, are put in contact, the two gradually diffusing one into the other in spite of the action of gravity. In some cases, however, as where ether and water are employed, the diffusion is only partial, this result arising from the fact that these two liquids are not miscible in all proportions. When solutions of various solid bodies are placed in contact, interdiffusion also takes place. On the results of his examination of the phenomena of diffusion of liquids and salts across porous membranes or septa, Graham founded a method of separating colloid from crystalloid bodies, which he called dialysis. Research Diffusion
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