Such chemical separation procedures (to remove unwanted radioactive isotopes of other elements) are also sometimes useful to improve the sensitivity of the analysis of gamma-ray emitters if necessary.
Whereas isotopes are the various forms of a single element (hence are a family of nuclides) and all have the same atomic number and number of protons, nuclides comprise all the isotopic forms of all the elements.
You find that there are two stable isotopes of copper having atomic weights of 63 and 65.
Until a few years ago, it was difficult to measure the number of gamma rays of a particular energy that were being emitted by a mixture of radioactive isotopes unless there were only a few such gamma rays with very different energies.
Silver-110m is one of two radioactive isotopes of silver that have the same mass.
Such tape may be “read” by a computer that can be programmed to use the data to calculate what radioactive isotopes are present and their quantities.
Most isotopeswill pass through the digestive tract or be excreted very quickly.
The time necessary for this decay to take place depends upon the isotopes present; each has a different decay rate (half-life).
Some isotopesare more hazardous because they are absorbed from the digestive tract and enter the metabolism of man and animals.
Surface contaminated food will contain a mixture of isotopes with some more hazardous than others, depending upon whether they are used by the body.
Internalization of radioactive isotopes will primarily occur via inhalation, ingestion, and contaminated wounds.
These two isotopes are absorbed in the body and used in the same way as calcium.
Meats and milk are the most vulnerable products because of the possibility for concentration of radioactive isotopes (Strontium, Cesium, and Iodine).
To evaluate the hazards; the isotopes contributing to the radioactivity must be identified.
Most manmade radioactive isotopes have much shorter half-lives, ranging from seconds or days up to thousands of years.
Beta-emitting isotopes are as harmful as alpha emitters if taken up by the body.
Stable isotopes have no distinguishing characteristic other than their mass; radioactive isotopes not only differ from their brothers in mass but also are characterized by unstable nuclei.
The earliest biochemical studies employing radioactive isotopes go back to 1924, when George de Hevesy used natural radioactive lead to investigate a biological process.
Radioactive Isotopes Radioactive isotopes occur as minor constituents in many natural materials, from which they can be concentrated by fractionation procedures.
After World War II, when radioactive isotopes were first available in appreciable quantities, autoradiography was further perfected through the efforts of such scientists as C.
In our studies of life processes, we are interested only in the radioactive isotopes that emit gamma rays or beta particles.
Let us now see how we can use radioactive isotopes to investigate the synthesis of RNA.
Radioactive Isotopes’ Value in Biological Studies To biologists, then, the essential feature in the use of radioactive isotopesis the possibility of preparing “labeled” samples of any organic molecule involved in biological processes.
Since the radiations emitted by radioactive isotopes can be detected and measured, we can readily follow a molecule tagged with a radioactive atom.
These radioactive isotopes are important because the corresponding stable isotopes of hydrogen, carbon, and phosphorus are present in practically all cellular components that are important in maintaining life.
Winston Churchill The various procedures in which radioactive isotopes play a major role have been applied to many studies and investigations in the fields of biology and medicine.
Just as a real microscope permits examination of the structural details of cells, isotopes permit examination of the chemical activities of molecules, atoms, and ions as they react within cells.
I think it's that isotopes aren't as stable as the basic elements.
That's why some of the isotopes of uranium can be split wide open in a chain reaction to make an atomic bomb, and .
However, because of interest in separating the isotopes of uranium by the electromagnetic method, work on the giant magnet continued at an even faster pace.
Individual elements are removed, and the radioactive isotopes of each element are identified by quantitative counting techniques.
The isotopes always have atomic weights that are close to, but not quite, whole numbers.
He and those who followed him located many isotopes and determined the frequency of their occurrence with considerable precision.
Thomson’s instrument was the first one capable of separating isotopes and such instruments came to be called “mass spectrometers”.
At first, it seemed that the only difference between isotopes might be in their radioactive properties and that only radioactive atoms were involved.
To avoid confusion, the average mass of the isotopesthat make up a particular element is still called the atomic weight of that element.
All 3 lead isotopes had the same atomic number of 82.
If this were so, there would be 3 lead isotopes that would differ not in radioactive properties, but in atomic weight.
In that case, one of the isotopes makes up very nearly all of it, while the others are present in such minor quantities that the average is hardly affected.
If neon had isotopesthen any element might have them.
It would be a matter of crucial importance if isotopes of neon could be found, for neon had nothing to do with any of the radioactive series.
One of these naturally radioactive isotopes is radioactive potassium, which is present to a small but significant extent in food, in human bodies, and in construction materials.
Future generations seeking to answer these questions will probably rely more on techniques using radioactiveisotopes than on any other methods known today.
Specifically, neither the parent isotopes can have been added nor the daughter isotopes removed by any process other than radioactive decay.
Each beam contains one isotope of the original material, because isotopes differ on the basis of their mass.
The normal isotopic composition of this element is accurately known, as it is for most elements, and the ratio of two of its isotopescan be expressed as A/B.
Isotopes of a given element have an identical number of protons but different numbers of neutrons in their nuclei.
It turns out to be a remarkable aspect of the Holmes-Houtermans calculation that the uranium-concentration terms cancel out in the equations and only the ratio of the isotopes and their decay constants need be considered.
Radioisotopes are isotopes that are unstable, or radioactive, and give off radiation spontaneously.
An equivalent statement is that nuclei ofisotopes have the same number of protons but different numbers of neutrons.
Atomic Energy Commission’s Divisions of Isotopes Development and Nuclear Education and Training, and the Oak Ridge Institute of Nuclear Studies.
For the diagnostician, small harmless quantities of many isotopes serve as tools to aid him in gaining information about normal and abnormal life processes.
How Isotopes Aid Medicine in Tracking Down Your Ailments, J.
The "explanation" of radioactivity led to the discovery of isotopes by Rutherford and Soddy in 1914, and with this discovery a revision of our idea of elements became necessary.
Also contained in rocks once molten are radioactive elements whose isotopes provide Earth scientists with an atomic clock.
Within these rocks, "parent" isotopes decay at a predictable rate to form "daughter" isotopes.
One way to tackle the problem was to add to the system some stable element that was chemically similar to the tiny traces of radioactive isotopes that might be produced through the bombardment of uranium.
If the radioactive isotopes included radium, that was conceivable.
Indeed, the uranium-238 nucleus tended to absorb slow neutrons without fission, and to go on to beta-particle production that formed isotopes of neptunium and plutonium.
Vast efforts were therefore made to separate the 2 isotopes and prepare uranium with a higher than normal concentration of uranium-235 (“enriched uranium”).
Over the next 30 years, isotopes were formed that contained more and more protons in the nucleus and therefore had higher and higher atomic numbers.
There are over 100 isotopes that will absorb neutrons and end by becoming an isotope of an element one higher in the atomic number scale.
Indeed, all the technetium isotopesare radioactive.
Would its isotopes also be raised in atomic number—in this case from 92 to 93?
At the moment of writing, isotopes of every element up to and including element 105 have been formed.
Slowly, it began to seem to Hahn that the failure to separate the barium and the radioactivity meant that the isotopes to which the radioactivity belonged had to be so much like barium as to be nothing else but barium.
A natural conclusion was that the isotopes producing the radioactivity belonged to an element that was chemically very similar to barium.
Also contained in rocks once molten are radioactive elements whose isotopes provide earth scientists with an atomic clock.
Incidentally, no isotopes have been discovered that leak pastward, though attempts are being made to synthesize them.
One of these isotopes of light tends to leak futureward through holes in space-time.
Isotopes are variant forms of atoms of the same element.
Bit by bit they divided the labor, checking in with Tiger by radio on the results of the isotopes studies he was running on the planet's surface.
Down on the surface Tiger had already inoculated a dozen of the healthy ones with various radioactive isotopes to help outline the normal metabolism and biochemistry of the people.
This “proton-electron theory” of nuclear structure accounted for isotopesvery nicely.
Illustration: Werner Heisenberg] The proton-neutron theory of nuclear structure could account for isotopes perfectly well, too.
When isotopes were first discovered this indeed seemed to be so.
How do dogs accumulate fallout isotopesin their bodies?
Produced by the Educational Broadcasting Corporation under the direction of the AEC’s Division of Isotopes Development.
They are designed so the radioisotopes they contain have similar distribution to the distribution of the isotopes expected in the real body.
Scanning devices are commonly used for noting the fate of tracer isotopesin medical diagnosis.
Illustration: Figure 15 Graphic evidence that a radioactive gas accidentally inhaled by a worker at an experimental reactor contained 3 radioactive isotopes of iodine.
When they found high levels of cesium-137 in lichens and caribou, they became interested in the body burdens of fallout isotopes in the Eskimos.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "isotopes" in a variety of sentences. We hope that you will now be able to make sentences using this word.
