Becquerel rays, discovery

Measurement of radioactiviry, as an analytical tool became possible after the discoveries of A.H.Becquerel(uranium radiation 1896), Pi re Marie Curie (polonium radium in 1898), Sir E. Rutherford (identification of Becquerel rays as consisting of alpha-, beta and gamma-particles) and of F.Soddy(phenomenon of nuclear disintegration, in 1902)... 

We considered some of the important experiments that led to the discovery and characterization of subatomic particles. Thomson s experiments on the behavior of cathode rays in magnetic and electric fields led to the discovery of the electron and allowed its charge-to-mass ratio to be measured. Millikan s oil-drop experiment determined the charge of the electron. Becquerel s discovery of radioactivity, the spontaneous emission of radiation by atoms, gave further evidence that the atom has a substructure. Rutherford s studies of how thin metal foils scatter a particles led to the nuclear model of the atom, showing that the atom has a dense, positively charged nucleus. 

X-radiation has been known from the very earliest days of nuclear science Rontgen named the rays in 1895, before Becquerel s discovery of radioactivity, and the classification of X-rays inevitably proceeded in a piecemeal fashion. Hence while Figure 1.18(a) is the sort of logical nomenclature one might pursue with today s hindsight, in practice this is only an approximation to the complicated real situation of Figure 1.18(c). Broadly, K , Kp, L and Lp fit the format more or less correctly, but the logical system fails even with some of these, and does so most decidedly with more distant transitions. 

Soon after Becquerel s discovery, a yoimg graduate student named Marie Sklodowska Ciuie (1867-1934), one of the first women in France to attempt doctoral work, decided to pursue the study of manic rays for her doctoral thesis. Her first task was to determine whether any other substances besides uranium (the... 

Soon after Becquerel s discovery, a young graduate student named Marie Sklodowska Curie (1867-1934) (one of the first women in France to pursue doctoral work) decided to study uranic rays for her doctoral thesis. Her first task was to determine whether any other substances besides uranium (the heaviest known element at the time) emitted these rays. In her search. Curie discovered two new elements, both of which also emitted uranic rays. Curie named one of her newly discovered elements polonium, after her home country of Poland. The other element she named radium, because of its high level of radioactivity. Radium is so radioactive that it gently glows in the dark and emits significant amounts of heat. Since it was clear that these rays were not unique to uranium. Curie changed the name of uranic rays to radioactivity. In 1903, Curie and her husband, Pierre Curie, as well as Becquerel were all awarded the Nobel Prize in physics for the discovery of radioactivity. In 1911, Curie received a second Nobel Prize, this time in chemistry, for her discovery of the two new elements. 

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. 

Roentgen s discovery of x-rays stimulated great interest in this new form of radiation worldwide. Antoine Henri Becquerel (1852-1908) accidentally discovered the process of radioactivity while he was studying x-rays. Radioactivity involves the spontaneous disintegration of unstable atomic nuclei. Becquerel had stored uranium salts on top of photographic plates in a dark drawer. When Becquerel retrieved the plates, he noticed the plates contained images made by the uranium salts. Bec-querel s initial discovery in 1896 was further developed by Marie Curie (1867-1934) and Pierre Curie (1859-1906). Marie Curie coined the word radioactive to describe the emission from uranium. 

A few months after Roentgen announced his discovery of X rays, the French physicist Antoine Henri Becquerel (1852—1908) experimented to see if they were emitted by phosphorescent substances—those that glow in the dark after being exposed to bright light. One substance that appeared to confirm the idea that phosphorescence resulted in X rays was uranium. When... 

Historically, the discovery of radioactivity dates back to 1896 when the French scientist Henri Becquerel believed that the afterglow observed in cathode ray tubes might be associated with phosphorescence, later realizing that this phenomenon was instead due to radiation. At first, this radiation was assumed to be similar to X-rays, but further research by Becquerel and a number of other notable scientists (including Marie Curie and Ernest Rutherford) revealed that the nature of this radiation was more complex. Subsequently, it emerged that there were three principal forms of radioactivity that result from different types of radioactive (nuclear) decay. 

The scientific development of radiation chemistry is reviewed from the discovery in 1895 of x-rays and radioactivity by Roentgen and Becquerel through to the present. 

The purpose of this article is to review the development of radiation chemistry which began with the discovery of x-rays by Roentgen(l) in 1895 and shortly afterwards of radioactivity by Becquerel(2), which in both cases Involved the observation of chemical change in photographic plates and luminescence in certain phosphors. Clearly, in the space available, the review will be restricted and subjective, but will, it is hoped, give the general framework in which the subject has developed. 

M. Genet, The Discovery of Uranic Rays A Short Step for Henri Becquerel but a Giant Step for Science, Radiochim. Acta 70/77, 3 (1995)... 

Natural radioactivity. Discovery by Becquerel, Isolation of polonium and radium from pitchblende, by the Curies. Alpha rays, beta rays, gamma rays. Effect of a magnetic field on these rays. Use of radium and other radioactive elements in the treatment of cancer. 

In 1896, when 76 Lavoisier elements were known [1], the discovery of the radioactivity of uranium by Henri Becquerel (1852-1908) [the first positive result in March 1896, after a series of negative experiments by other people studying fluorescent materials, subsequent to a rather far-fetched remark in December 1895 by the mathematician Henri Poincare (1854-1912) that since X-rays induce a strong fluorescence in BaPt(CN)4- 4H2O, fluorescent solids may... 

The scientific world, at this time, was all agog with ROntgen s discovery of 1895 °f a new set of rays, the so-called X or RSntgen rays, emanating from the glass walls of tubes where bombardment by cathode rays occurs. The time was therefore ripe for Becquerel s results and scientists were not slow to turn them to good account. 

Stimulated by Rontgen s discovery of x-rays, Henri Becquerel (1852-1908) postulated a relationship between x-rays and fluorescence. He placed a variety of fluorescent crystalline samples in contact with photographic plates that were... 

In 1896, Henri Becquerel (Fig. 3.18) made the serendipitous discovery of yet another unexpected phenomenon, revealing the existence of invisible radiations with wavelengths shorter than those of x rays. He had found that crystals of the... 

---