D Arsonval

The concept of OTEC was first envisioned by the French physicist Jacques-Arsene d Arsonval, in 1881. The first working OTEC system was built in Cuba in 1930, by the physicist Georges Claude, who also invented the neon lamp. 

The coil (wound on a light metal former) can be suspended by a fine strip of phosphor bronze between the pole pieces. Attached to this suspension is a small mirror which reflects on to a scale a beam of light which is focused upon it. An instrument of this kind is known as a D Arsonval galvanometer and is used in potentiometer circuits and various methods of measurement of resistance. 

One might have thought that d Arsonval s discovery would be sufficient to generate further studies of brain function by magnetic stimulation, but the technical solutions to this had to wait for the best part of the twentieth century until 1985 when Anthony Barker and colleagues at the University of Sheffield successfully stimulated the motor cortex and pro-... 

Figure 10.3. d Arsonval and colleagues showing the apparatus used to induce visual phosphenes. This photo was taken in 1911. 

M. d Arsonval, a member of the Academy of Sciences, has just presented a lecture before said Academy concerning the discovery of rays emanating from the human body and made visible by means of radium lighting [lumiere du radium]. Two researchers from the city of Nancy, Messers Charpentier and Blondlot, are the first who have used this procedure to perceive these rays, which they have called N after the initial letter of the word Nancy. Blondlot recounts how, while making a study of X-rays, they began to notice the emission of other rays which... 

Charles Edouard Brown-Sequard and J. d Arsonval, article in Comptes Rendus de la Societe de Biologie, 1891... 

Attempts by 0. E. Brown-Sequard and A. d Arsonval, and S. Merkel have been made to show that the depressed feeling and uneasiness experienced in crowded rooms is not solely due to the diminution of oxygen, and increase of carbon dioxide, but is rather due to the presence of a volatile organic poison in the expired air. This hypothesis was contested by A. Dastre and P. Loye, A. Russo-Giliberti and G. Alessi, D. H. Bergey, S. W. Mitchell and J. S. Billings, G. von Hofmann-Wellenhof, and K. B. Lehmann and F. Jessen. 0. Wurster, and T. Cramer attributed the injurious effects to the presence of nitrates. 

The first plant devised for supplying oxygen was that of D Arsonval, of the Royal College of France (1885), who employed a 30 per cent, solution of potash as electrolyte. 

Resistance to Heat Test(Epreuve de la resistance a la daleur). This Fr "Official test for detn of stability of NC Of of smokeless propellauts is conducted in a theffnostaiicslly coutfolled oven, "type d Arsonval. NC is tested at 108. d propellants at 108.3 nnd 109°> blue litmus paper. The test is con-... 

In their 1906 paper to the Academie des Sciences in Paris (almost a century ago), Bordas and d Arsonval [1] demonstrated for the first time that it was possible to dry a delicate product from the frozen state under moderate vacuum. In that state it would be stable at room temperature for a long time and the authors described, in a set of successive notes, that this technique could be applied to the preservation of sera and vaccines. Freeze-drying was then officially borne, despite its having been in use centuries ago by the Inca who dried their frozen meat in the radiant heat of the sun in the rarified atmosphere of the Altiplano. 

J.A. D Arsonval Interrupteur electrolytique. Comptes rendus hebdomadaires des stances de I Acadtmie des Sciences CXXVIII (1899), p. 529. 

The Cahn electrobalance is a sensitive, accurate, reliable, and easily operated balance which is based on a D Arsonval galvanometer, with the sample... 

Several types of readout devices are found in modern instruments. Some of those devices include the D Arsonval meter, digital meters, recorders, cathode-ray lubcs, LCD panels, and computer displays. 

Around 1900, it was well-known that large high-frequency currents of more than 1 A could pass through the human body with only heat sensation (Arsine d Arsonval, 1893), but that small low-frequency currents excited the nerves without heat effects. 

Where measurements of current in massive structures having extremely low longitudinal resistances are required, and to avoid the errors referred to in the previous paragraph, a refinement of the zero-resistance ammeter is used. Instead of a voltmeter, a high-sensitivity D Arsonval galvanometer with a centre-zero scale is used. The connections remain essentially the same as those in Fig. 10.47, except that a reversing switch is incorporated so that the current 4 can be applied first in one direction and then in the other. 

A scientific curiosity for almost 40 years after the publication of Bordas and d Arsonval in 1906, freeze-drying, later called lyophilization by Earl Flosdorf at the time of World War II, has bloomed again within the past 20 years to become an almost unavoidable technology to preserve rare and sensitive biochemicals and drugs. Concomitantly, new challenges appeared in basic and applied engineering fields and required more and more sophisticated approaches. 

Freeze-drying (Jacques Arsene d Arsonval and Geoi e Bordas) D Arsonval and Bordas invent freeze-drying, but the practice is not commercially developed until after World War II. 

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