radioactivity ,

Critically invisible, modern revolt, like X-rays and radioactivity, is perceived only by its effects at more materialistic social levels, where it is called delinquency.

Owing to its scarcity, high price and radioactivity, actinium has no significant industrial use.

Owing to its strong radioactivity, actinium glows in the dark with a pale blue light, which originates from the surrounding air ionized by the emitted energetic particles.

For example, in the 19th century, the Sun appeared to be no more than 20 million years old, but the Earth appeared to be no less than 300 million years ( resolved by the discovery of nuclear fusion and radioactivity, and the theory of quantum mechanics ); or current attempts to resolve theoretical differences between quantum mechanics and general relativity.

If the molecules to be separated contain radioactivity, for example in DNA sequencing gel, an autoradiogram can be recorded of the gel.

Helium is not subject to steam explosions, resists neutron absorption leading to radioactivity, and does not dissolve contaminants that can become radioactive.

Because of its cost and radioactivity, experimental chemical research is seldom performed with radon, and as a result there are very few reported compounds of radon, all either fluorides or oxides.

He also devised one of the first instruments for the study of nuclear radioactivity, the spinthariscope.

In 1903, Crookes turned his attention to the newly discovered phenomenon of radioactivity, achieving the separation from uranium of its active transformation product, uranium-X ( later established to be protactinium ).

If an internal monitor detects radioactivity, the flask is shattered, releasing the poison that kills the cat.

Despite its radioactivity, thorium fluoride ( ThF < sub > 4 </ sub >) is used as an antireflection material in multilayered optical coatings.

Before the discovery of radioactivity, uranium was primarily used in small amounts for yellow glass and pottery glazes, such as uranium glass and in Fiestaware.

Natural processes which produce trace radioisotopes include cosmic ray bombardment of stable nuclides, ordinary alpha and beta decay of the long-lived heavy nuclides, Thorium-232, Uranium-238, and Uranium-235, spontaneous fission of natural Uranium-238, and nuclear transmutation reactions induced by natural radioactivity, such as the production of Plutonium-239 and Uranium-236 from neutron capture

Failure to meet objectives, along with the realization of the dangers of nuclear fallout and other residual radioactivity, and with the enactment of various agreements such as the Partial Test Ban Treaty and the Outer Space Treaty, has led to the termination of most of these programs.

There followed a period of intense research in radioactivity, including the discovery of additional radioactive elements thorium, polonium and radium, the latter two by Becquerel's doctoral student Marie Curie and her husband Pierre Curie.

The SI unit for radioactivity, the becquerel ( Bq ), is named after him.

The main sources of heat are the primordial heat and radioactivity, although there are also contributions from phase transitions.

Researchers at nearby Dickinson College — which had radiation monitoring equipment sensitive enough to detect Chinese atmospheric atomic weapons testing — collected soil samples from the area for the ensuing two weeks and detected no elevated levels of radioactivity, except after rainfalls ( likely due to natural radon plate out, not the accident ).

Had there been elevated releases of radioactivity, increased levels of Iodine-131 and Cesium-137 would have been expected to be detected in cattle and goat's milk samples.

The Curie ( symbol Ci ) is a non-SI unit of radioactivity, named after Marie and Pierre Curie .< ref >

Marie Curie, famous for her pioneering work in the field of radioactivity, died of aplastic anemia after working unprotected with radioactive materials for a long period of time ; the damaging effects of ionizing radiation were not then known.

Since nuclear fission creates radioactivity, the reactor core is surrounded by a protective shield.

The modern electronic scintillation counter was invented in 1944 by Sir Samuel Curran whilst he was working on the Manhattan Project at the University of California at Berkeley, and it is based on the work of earlier researchers reaching back to Antoine Henri Becquerel, who is generally credited with discovering radioactivity, whilst working on the phosphorescence of certain uranium salts ( in 1896 ).

This essentially means that the human is now the source of the radioactivity, rather than the medical imaging devices such as X-Ray or CT.

Nuclear chemistry is the subfield of chemistry dealing with radioactivity, nuclear processes and nuclear properties.