Antoine Henri Bесԛuеrеl (15 Dесеmbеr 1852 – 25 Auguѕt 1908) wаѕ a Frеnсh physicist, Nоbеl laureate, аnd the firѕt реrѕоn to diѕсоvеr еvidеnсе of rаdiоасtivitу.
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One hypothesis which presents itself to the mind naturally enough would be to suppose that these rays, whose effects have a great similarity to the effects produced by the rays studied by M. Lenard and M. Röntgen, are invisible rays. Henri Becquerel
One hypothesis which presents itself to the mind naturally enough would be to suppose that these rays, whose effects have a great similarity to the effects produced by the rays studied by M. Lenard and M. Röntgen, are invisible rays.
It is important to observe that it appears this phenomenon must not be attributed to the luminous radiation emitted by phosphorescence. Henri Becquerel
It is important to observe that it appears this phenomenon must not be attributed to the luminous radiation emitted by phosphorescence.
I developed the photographic plates on the 1st of March, expecting to find the images very weak. Instead the silhouettes appeared with great intensity. Henri Becquerel
I developed the photographic plates on the 1st of March, expecting to find the images very weak. Instead the silhouettes appeared with great intensity.
in the same conditions and through the same screens, but sheltered from the excitation of incident rays and kept in darkness, still produce the same photographic images ... [when kept from 26 Feb 1896] in the darkness of a bureau drawer. Henri Becquerel
in the same conditions and through the same screens, but sheltered from the excitation of incident rays and kept in darkness, still produce the same photographic images ... [when kept from 26 Feb 1896] in the darkness of a bureau drawer.
The same [double sulfate of uranium and potassium] crystalline crusts, arranged the same way [as reported to the French academy on 24 Feb 1896] with respect to the photographic plates. Henri Becquerel
The same [double sulfate of uranium and potassium] crystalline crusts, arranged the same way [as reported to the French academy on 24 Feb 1896] with respect to the photographic plates.
I will insist particularly upon the following fact, which seems to me quite important and beyond the phenomena which one could expect to observe. Henri Becquerel
I will insist particularly upon the following fact, which seems to me quite important and beyond the phenomena which one could expect to observe.
One must conclude from these experiments that the phosphorescent substance in question emits rays which pass through the opaque paper and reduces silver salts. Henri Becquerel
One must conclude from these experiments that the phosphorescent substance in question emits rays which pass through the opaque paper and reduces silver salts.
One can repeat the same experiments placing a thin pane of glass between the phosphorescent substance and the paper, which excludes the possibility of chemical action due to vapors which might emanate from the substance. Henri Becquerel
One can repeat the same experiments placing a thin pane of glass between the phosphorescent substance and the paper, which excludes the possibility of chemical action due to vapors which might emanate from the substance.
If one places between the phosphorescent substance and the paper a piece of money or a metal screen pierced with a cut-out design, one sees the image of these objects appear on the negative. Henri Becquerel
If one places between the phosphorescent substance and the paper a piece of money or a metal screen pierced with a cut-out design, one sees the image of these objects appear on the negative.
When one then develops the photographic plate, one recognizes that the silhouette of the phosphorescent substance appears in black on the negative. Henri Becquerel
When one then develops the photographic plate, one recognizes that the silhouette of the phosphorescent substance appears in black on the negative.
One places on the sheet of paper, on the outside, a slab of the phosphorescent substance, and one exposes the whole to the sun for several hours. Henri Becquerel
One places on the sheet of paper, on the outside, a slab of the phosphorescent substance, and one exposes the whole to the sun for several hours.
I was able to perform the following experiment: One wraps a Lumière photographic plate with a bromide emulsion in two sheets of very thick black paper, such that the plate does not become clouded upon being exposed to the sun for a day. Henri Becquerel
I was able to perform the following experiment: One wraps a Lumière photographic plate with a bromide emulsion in two sheets of very thick black paper, such that the plate does not become clouded upon being exposed to the sun for a day.