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| | helium |
 | | The only known helium extraction plants, outside the United States, in 1996 were in Eastem Europe (Poland), Russia, China, and India. |
 | | Using liquid helium, Kurti and co-workers, and others, have succeeded in obtaining temperatures of a few microkelvins by the adiabatic demagnetization of copper nuclei, starting from about 0.01 K. Seven isotopes of helium are known. |
 | | Liquid helium (He4) exists in two forms: He4I and He4II, with a sharp transition point at 2.174 K (3.83 cm Hg). |
| www.speclab.com /elements/helium.htm (863 words) |
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