Thursday, June 12, 2014

ARTICLE FROM BLOG



POLONIUM-210: THE MOST DEADLY POISON
Some of these days, the ranks of the media highlights about the death of Palestinian leader Yasser Arafat, nine years ago. Arafat was allegedly killed by polonium-210, which has also been used to kill Kremlin spy, Alexander Litvinenko in 2006. What is a poison polonium-210?
Before discussing the polonium-210, we will discuss first about polonium. Polonium is the element of atomic number 84 and includes the VIA group. Polonium has electron configuration [Xe] 6s2 4f14 5d10 6p4. This element is a radioactive element. Polonium has 33 isotopes, which the wight from 186 to 226 nucleons. The most stable natural isotope is polonium-210 with a half-life 138 days. Meanwhile, overall. Either natural or synthetic isotopes, 209Po has the longest half life time, which is 103 years old. One of these isotopes is polonium-210 or abbreviated 210Po, which we will discuss in this post.
210Po is an alpha ray emitter with a half-life 138.376 days, with by-products are isotopes of lead-206 (206Pb). One milligram of 210Po can emit alpha particles every second is equivalent to 5 grams of radium-226 (226Ra). A few curies  (1 curie equals 37 gigabecquerel ) 210Po emit a blue color caused by the excitation (loss of electrons) to the surrounding air . One gram of  210Po generates 140 watts of power. Is because  it emits a lot of alpha particles , which can be stopped in a short distance with a medium and expend energy,  210 Po has been used as an efficient heat source for charging the  thermoelectric cells in  artificial satellites , as an example,  the energy source of  210Po is also used in plant  Lunokhod  is built on  the surface of the moon , to keep the warmth inside during the evening components in months. Several  containing antistatic brush to  500 microcuries (19 MBq)  210Po as a source of ions to neutralize static electricity in materials like photographic film.  210Po is also used as an  initiator  for the  atomic bomb through the reaction (α, n) with  beryllium .
Most of the decomposition of  210Po followed the release of alpha particles, rather than the release of alpha particles and gamma rays. approximately one than 100.000 decay produces gamma rays. The rate of formation of a low gamma ray this causes this isotope is very difficult to find and identify. Compared with gamma-ray spectroscopy, alpha spektrospok is the best way to track this isotope. 210Po appears very little in nature, where the isotope is an isotope mid cycle radium decay chain (also known uranium cycle). This isotope is also obtained via beta decay of bismuth-210 (Bi-210) .
210Po is extremely toxic, with only one microgram is enough to kill an adult (250.000 times more toxic  than hydrogen cyanide  is measured by its mass ).  210Po was used to kill the agent who spied on the Kremlin, Alexander V. Litvinenko  in  2006  and recently , the analysis of the body of Yasser Arafat, in November 2013 led to the murder indication polonium-210.
Sources:
"Isotopes of polonium" (http://en.wikipedia.org/wiki/Isotopes_of_polonium, accessed on November 9, 2013)
"polonium" (http://en.wikipedia.org/wiki/Polonium, accessed on November 9, 2013)

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