Becquerel effect

The electrochemical photovoltaic effect was discovered in 1839 by A. E. Becquerelt when a silver/silver halide electrode was irradiated in a solution of diluted HN03. Becquerel also first described the photogalvanic effect in a cell consisting of two Pt electrodes, one immersed in aqueous and the other in ethanolic solution of Fe(C104)3. This discovery was made about the same time as the observation of the photovoltaic effect at the Ag/AgX electrodes. The term Becquerel effect often appears in the old literature, even for denoting the vacuum photoelectric effect which was discovered almost 50 years later. The electrochemical photovoltaic effect was elucidated in 1955 by W. H. Brattain and G. G. B. Garrett the theory was further developed... 

Photoconductivity in photographic systems. II. Some applications to the phenomena of supersensitization, desensitization and the Becquerel effect. J. chem. Physics 15, 539 (1947)-... 

Photoelectrochemical effect involves production of a voltage and an electric current when light falls on a semiconductor electrode immersed in an electrolyte solution and connected to a counter electrode (Becquerel, 1839). Working with germanium electrodes, Brattain Garrett (1955) showed that the Becquerel effect was due to the formation of a semiconductor-electrolyte junction. The idea of using an illuminated... 

BECQUEREL EFFECT, A photographic effect discovered by E, Becquerel (1895). Experimenting with the daguerreotype process. Becquerel found that a plate will produce a direct (positive) image if exposed first to diffuse daylight. See also Photochemistry and Photolysis and Photography and Imagery. 

An old-known characteristic of U022 is the Becquerel effect, that platinum (or other) electrodes immersed in illuminated and dark samples of the same composition show a potential difference. Since it is usually within the range 0.01 to 0.1 V, it has mainly academic interest, like several other photo-electrochemical potentials89. There has been some discussion as to whether traces of organic molecules mediate this, not particularly reproducible, effect22. ... 

Becquerel effect. The electromotive force resulting from unequal illumination of two similar electrodes immersed in an electrolyte. 

Muller R. H. and Spector A. (1932), The Becquerel effect as a special case of the barrier-layer photoelectric cell , Phys. Rev. 41, 371-372. 

To choose the most effective working pigment from that abundance is extremely difficult, especially as the theoretical assumptions for this choice are almost none. At certain stages one has to use intuitively guided screening to detect certain patterns that will eventually lead to the creation of a more or less acceptable theoiy. Thus, in comparison of the photocatalytic activity (the photovoltaic Becquerel effect) of thin films of TPC with different macrocycle structure it was noted that the maximum photocurrent (y and photopotential (U j ) are given... 

Photoactivity of the films were eompared by Becquerel effect value, measuring Upjj relatively a saturated Ag/AgCl electrode in aerated 1.0 N KCl electrolyte, changing the pH from 1 to 14 by titration with 1.0 N KOH or HCl solution. Pigmented electrodes were illuminated with an arc xenon lamp DKSSh-120 with a stabilized power supply, the light output in the plane of the electrode was 100 mW/cm . For measurement of the quantum yield on a current T pigment films with thickness d from 2 to 300 nm were applied on polished quartz substrates coated with a conductive layer of platinum. The T value was determined from a ratio... 

The photovoltaic effect, where an internal elecromotive force is created, was discovered by Becquerel (106) in 1839 in an electrolyte with selenium but the effect in a metal—Se contact was first reported by Adams and Day (107) in 1876. The first practical photovoltaic cell was constmcted by Uljanin (108) in 1888. 

In 1839 Alexandre-Edmtmd Becquerel, a French experimental physicist, did the earliest recorded experiments with the photovoltaic effect. Becquerel discovered the photovoltaic effect while experimenting with an electrolytic cell made up of two metal... 

Williams R (1960) Becquerel photovoltaic effect in binary compounds. J Chem Phys 32 1505-1514... 

Lind (1961) defines radiation chemistry as the science of the chemical effects brought about by the absorption of ionizing radiation in matter. It can be said that in 1895, along with X-rays, Roentgen also discovered the chemical action of ionizing radiation. He drew attention to the similarity of the chemical effects induced by visible light and X-rays on the silver salt of the photographic plate. This was quickly followed by the discovery of radioactivity of uranium by Becquerel in 1896. In 1898, the Curies discovered two more radioactive elements—polonium and radium. 

In 1898 Marie Sklodowska Curie (1867-1934), while experimenting with thorium and uranium, coined the word radioactivity to describe this newly discovered type of radiation. She went on to discover polonium and radium. Madam Curie and her husband Pierre Curie (1859—1906), who discovered the piezoelectric effect, which is used to measure the level of radiation, and Henri Becquerel jointly received the 1903 Nobel Prize in Physics for their work on radioactivity. 

Becquerel AE (1839) Memoire sur les effects d electriques produits sous Linfluence des rayons solaires. Comptes Rendus de L Academie des Sciences 9 561-567. Republished Becquerel AE (1841) Annalen der Physick und Chemie. 54 35-42... 

RADIOACTIVITY. The spontaneous disintegration of the nucleus of an atom with the emission of radiation. This phenomenon was discovered by Becquerel in 1896 by the exposure-producing effect on a photographic plate by pitchblende (uranium-containing mineral) while wrapped m black paper in the dark, Soon after this, it was found that uranium minerals and uranium chemicals showed more radioactivity than could be accounted for by the uranium content. About the same dmc. radioactivity of thorium minerals and thorium chemicals was also discovered. 

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