Davy Humphrey

Davy, Humphrey, 501 de Broglie, Louis, 138 Debye, Peter, 276 Decay... 

Daniell, John Fredrick, 180 Davy, Humphrey, 72, 73, 156, 176 de Broglie, Louis, 40 de Buffon, Comte, 72 de Fourcroy, Antoine Francois, 27 de Mestral, George, 299 de Morveau, Guyton, 27 Democritus, 9, 10, 47, 71 Diocletian, 12 Dobereiner, Johann, 61, 62... 

Gr. barys, heavy) Baryta was distinguished from lime by Scheele in 1774 the element was discovered by Sir Humphrey Davy in 1808. 

It is not certain whether Sir Humphrey Davy (Fig. 1-7) knew of these considerations. He accepted a commission from the Admiralty for the protection of copper-clad wooden ships, which had been introduced in 1761. During his numerous laboratory experiments, he discovered the cathodic protection of copper by zinc or iron [3]. Davy had already put forward the hypothesis in 1812 that chemical and electrical changes are identical or at least arise from the same material property. He believed that chemical reaction forces could be reduced or increased by altering the electric state of the material. Materials can combine only if they have different electric charges. If an originally positive material can be artificially negatively... 

Also in 1815, but before Davy presented his first lamp to the public, George Stephenson (one of the pioneers in the development of the steam locomotive) quite independently was also working on a safe miner s lamp. He discovered during his experiments that flame produced by a particular gas at a given concentration will not pass through a tube smaller than a certain diameter. While most people have heard of Davy s lamp (it seems that Sir Humphrey received all the credit), it was actually Stephenson s discov-... 

In recent years it has been regarded as somewhat passe to refer to Sir Humphrey Davy in a text on cathodic protection. However, his role in the application of cathodic protection should not be ignored. In 1824 Davy presented a series of papers to the Royal Society in London in which he described how zinc and iron anodes could be used to prevent the corrosion of copper sheathing on the wooden hulls of British naval vessels. His paper shows a considerable intuitive awareness of what are now accepted as the principles of cathodic protection. Several practical tests were made on vessels in harbour and on sea-going ships, including the effect of various current densities on the level of protection of the copper. Davy also considered the use of an impressed current device based on a battery, but did not consider the method to be practicable. 

McDonagh AM, Humphrey MG, Samoc M, Luther-Davies B (1999) OrganometaUics 18 5195... 

Humphrey Davy Mixture of coal gas and air makes platinum wire white hot... 

Gas hydrates are a special form of clathrates. Here water is the host molecule. The first gas hydrate (with chlorine) was described in 1818 by Sir Humphrey Davy. Naturally-occurring gas hydrates in Siberia are methane hydrates. 

Boron itself was first produced in 1808 by Sir Humphrey Davy, who carried out the electrolysis of molten boric acid. The reduction of boric acid by potassium was used as a preparative method by Gay-Lussac and Thenard in 1808, and reduction of B203 by magnesium was the method used by Moissan in 1895. 

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