tag:blogger.com,1999:blog-22973357.post576203535174969816..comments2023-09-27T07:44:19.769-04:00Comments on Sabine Hossenfelder: Backreaction: Technetium-99Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comBlogger17125tag:blogger.com,1999:blog-22973357.post-765692632123224922014-03-28T14:24:37.350-04:002014-03-28T14:24:37.350-04:00@eagle
It's possible for all elements to even...@eagle<br /><br />It's possible for all elements to eventually decay. I do not know how anyone would be able to analyze the decay of something that has a trillion year half life- it would appear to be "stable" to us.<br /><br />There is also the fact that spacial fields may mediate decay patterns which would allow for different decay rates. Introduction to the concept: http://brianhttps://www.blogger.com/profile/06132438532341848915noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-56364747472292439652010-03-31T17:25:45.804-04:002010-03-31T17:25:45.804-04:00@Neil' - don't forget about Promethium. I...@Neil' - don't forget about Promethium. It and Technetium both have no stable isotopes, and they are both lower in Z than Bismuth.<br /><br />The idea of stability raises an interesting point - at what point do we consider something to be stable? What if something could decay, but its half-life is so long and it is present in such small amounts that observation of decay during our Unknownhttps://www.blogger.com/profile/16580956456826200094noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-85823973248852673132010-01-12T15:22:53.785-05:002010-01-12T15:22:53.785-05:00Why isn't U-238 used instead of U-235?Why isn't U-238 used instead of U-235?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-49702763871293940982008-11-16T17:53:00.000-05:002008-11-16T17:53:00.000-05:00I used to live close to Petten. I've been there on...I used to live close to Petten. I've been there once to look at their reactor. It looked really old and almost all the buildings around main reactor building were deserted. One marvelous thing I saw that I will never forget was that you could see the Cerenkov radiation as you looked down through the water. I know they did a lot of medical experiments but I never knew they produced Molybdenum-99. Hum Bughttps://www.blogger.com/profile/02045005575382002339noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-33280244560310423502008-11-16T02:03:00.000-05:002008-11-16T02:03:00.000-05:00Technitium 99 is used for heart function measureme...Technitium 99 is used for heart function measurements too. The test itself typically takes about 20 minutes and the preparatory work of removing a blood sample, tagging it with the 99 Tc marker, and reinjecting the blood takes about another 30 minutes. Except for the apparently nail-sized needle used to extract the large blood sample the procedure is painless!<BR/> A highly multipoint detector isAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-23587568780523030132008-11-14T10:28:00.000-05:002008-11-14T10:28:00.000-05:00For the record: I said " Yes, technetium is weird ...For the record: I said " Yes, technetium is weird because of being unstable even as element 43 and way below polonium (the first all-radioactive element, unless you say that all Bi has a very long HL, or does it?)" Well Tc itself is the first ARE. But it is true that Bismuth is the next ARE, not Po, since all isotopes are radioactive (see http://en.wikipedia.org/wiki/Isotopes_of_bismuth.) But Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-80495698666026036332008-11-14T06:25:00.000-05:002008-11-14T06:25:00.000-05:00Hi Stefan,Yes Chalk River was one of the facilitie...Hi Stefan,<BR/><BR/>Yes Chalk River was one of the facilities set up for and during the Manhattan Project after the signing of the <A HREF="http://en.wikipedia.org/wiki/Quebec_Agreement" REL="nofollow">Quebec Agreement</A> between the U.S., Britain and Canada. Canada’s initial contribution was in the mining and processing of Uranium along with related nuclear reactor research. After the war Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-3966088712301778422008-11-13T18:51:00.000-05:002008-11-13T18:51:00.000-05:00Hi Phil,thanks for pointing out the Canadian versi...Hi Phil,<BR/><BR/>thanks for pointing out the Canadian version of the story! In the radio feature I head heard, it was mentioned that replacement for the Mo missing from Petten actually is coming from a 53 years old reactor in Canada, so that must be Chalk River. Interesting that it had been shut down also just earlier this year!<BR/><BR/>Chalk River goes back to Manhattan Project, doesn't it? stefanhttps://www.blogger.com/profile/09495628046446378453noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-6909639690567112562008-11-13T06:37:00.000-05:002008-11-13T06:37:00.000-05:00Hi Stefan,“But this will be the stuff of another p...Hi Stefan,<BR/><BR/>“But this will be the stuff of another post.”<BR/><BR/>I must apologize for addressing the wrong author.Also,as mentioned I am curious of what your follow might be to this. To be truthful I was expecting you to perhaps announce the <A HREF="http://www.npr.org/templates/story/story.php?storyId=96844982" REL="nofollow">demise of Phoenix</A> with it finally falling victim to thePhil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-72369088666783843212008-11-12T23:21:00.000-05:002008-11-12T23:21:00.000-05:00It's interesting how "exotic" elements seem to pop...It's interesting how "exotic" elements seem to pop up more and more in every day life. Smoke detectors use americium, batteries use lithium, and cell phones use tantalum. I grew up in a world of wood and metal, but we are in a golden age of materials science. Who knows how soon the typical home with have the whole periodic table?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-81372287242143019182008-11-12T22:53:00.000-05:002008-11-12T22:53:00.000-05:00Ah yes, Tedhnitium 99 m and I are better acquainte...Ah yes, Tedhnitium 99 m and I are better acquainted than I would prefer. I had wondered how one kept the stuff for shipment, since it won't exactly stay fresh in the fridge. The MO I guess, is the Mo, which lives long enough for shipment.CapitalistImperialistPighttps://www.blogger.com/profile/17523405806602731435noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-14981566026508205452008-11-12T15:29:00.000-05:002008-11-12T15:29:00.000-05:00Very interesting post on Technetium, thanks Stefan...Very interesting post on Technetium, thanks Stefan.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-77597895465527002682008-11-12T13:08:00.000-05:002008-11-12T13:08:00.000-05:00Neutrinoless double beta-decay of Mo-100 is also a...Neutrinoless double beta-decay of Mo-100 is also a barrel of fun! Safe for the kids: t_1/2 = 4.6x10^23 years (NEMO3). A clever approach uses scintillator crystal CaMoO4 with Mo-100. The source is also the detector.<BR/><BR/>Fewer than 2.2x10^14 technetium atoms/cm^2, about 55 ppm of KTcO4 in water, lends remarkable corrosion resistance to mild carbon steel. Alas, that is about 3 x 10^6 Bq/g Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-33172871849870578502008-11-12T12:55:00.000-05:002008-11-12T12:55:00.000-05:00Yes, technetium is weird because of being unstable...Yes, technetium is weird because of being unstable even as element 43 and way below polonium (the first all-radioactive element, unless you say that all Bi has a very long HL, or does it?) I am sure this is understood in terms of nuclear shell theory. Few people "on the street" have ever heard of it.<BR/><BR/>But Tc is also important for <I>chemical</I> reasons, the latter being less well-known. Neil Bateshttps://www.blogger.com/profile/04564859009749481136noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-62063292817288027762008-11-12T12:33:00.000-05:002008-11-12T12:33:00.000-05:00Stefan:what a strange element is technetium in the...<B>Stefan</B>:<I>what a strange element is technetium in the first place, as without stable isotopes, it marks a gap in the middle of the periodic table?</I><BR/><BR/>I'm wondering. Because I have a special interest with the elements and the <A HREF="http://en.wikipedia.org/wiki/Periodic_table" REL="nofollow" TITLE="a tabular method of displaying the chemical elements">periodic table</A> PlatoHagelhttps://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-27400189424964799702008-11-12T09:33:00.000-05:002008-11-12T09:33:00.000-05:00Credits go to Stefan...Credits go to Stefan...Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-79070118018920002582008-11-11T22:02:00.000-05:002008-11-11T22:02:00.000-05:00Hi Bee,That was quite the explanation and I ‘ll be...Hi Bee,<BR/><BR/>That was quite the explanation and I ‘ll be curious where you are leading to on this. This whole medical isotope shortage thing <A HREF="http://www.cbc.ca/news/background/health/isotopes.html" REL="nofollow">first began in Canada</A> last year when a safety inspector ordered the shutdown of the reactor in Chalk River Ontario were they produce the material you explain here for Phil Warnellhttps://www.blogger.com/profile/15671311338712852659noreply@blogger.com