The phrase "a heavy element" is correct and usable in written English.
It can be used in contexts related to chemistry, physics, or discussions about materials that have a high atomic mass or density.
Example: "Lead is considered a heavy element due to its high density and atomic weight."
Alternatives: "a dense element" or "a substantial element".
To assume, however, that a heavy element is thus restricted in distribution appears to me to present difficulties.
Lazard's Rucker claimed not: "A lot of the orders [for shares] that go into the books... there is a heavy element of gaming.
Plutonium is a heavy element and not easily dispersed, he said, so higher levels outside the reactor suggested a wider leak.
The increase in deposition rate is achieved by sputtering yield amplification through doping the sputtering target by a heavy element.
It was found that various elements, when bombarded by neutrons, undergo fission a type of nuclear reaction that occurs when the nucleus of a heavy element is split into two nearly equal smaller fragments.
Although phosphorus-containing heterocycles have long been known, the heterocyclic chemistry of arsenic, antimony, and bismuth has made significant progress only in recent years because of the decreased stability of heterocycles involving a heavy element.
In contrast when a heavier element is incorporated a {100} texture is observed.
A lower residual compressive stress (typically −1.8 GPa) is observed when one of the bi-layers is dominated by a heavier element.
When light elements such as deuterium--a hydrogen with an extra neutron--collide with each other with sufficient force, they can stick together, creating a heavier element.
Also, in the case of the TEM micrographs, the samples anodized in the presence of PTA showed intermittent dark spots which can be attributed to the presence of a heavier element compared to Ti indicating the incorporation of WOx.
As strontium is a heavier element than calcium, its presence in bone could lead to an overestimation of BMD measurement.
