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careysub
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Mood: Lowest quantum state

 Quote: Originally posted by neptunium the natural reactor in Africa is the proof of what nature can do alone.. so if Pu244 cannot be generated, where does that leaves us for Unbibium 292 and Marinovs claim? exactly!!

He is looking for primordial super-heavy elements that may have survived from the last supernova explosion in the r-process to enrich the solar system at its birth, not ones made on Earth by natural fission or cosmic ray neutrons. Since Sm-146, with a 108 million year half-life has survived from that event, then other 100 million year half-life nuclides will as well.

But without an inert natural carrier (stable samarium) there is no known way for the them to become concentrated to detectable levels, if they exist.

Think about the samarium situation. Stable isotope ratios vary throughout the solar system at the level of a few percent or less.* So any ancient samarium, however far it has decayed today, will still be present in any modern samarium sample, if there is any at all. This is really helpful in finding it.

When looking for new elements, which may exist on Earth at the same quantity, we do not have this convenient concentration and identification mechanism.

*This variation is due to fractionation processes after the early nebula collapsed (and which is thought to have been thoroughly mixed and quite uniform).
S.C. Wack
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My Great-Great-Aunt Discovered Francium. And It Killed Her.
By VERONIQUE GREENWOOD DEC. 3, 2014
http://www.nytimes.com/2014/12/07/magazine/my-great-great-au...

Interesting IMHO.

"You're going to be all right, kid...Everything's under control." Yossarian, to Snowden
neptunium
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Quote: Originally posted by careysub
 Quote: Originally posted by neptunium the natural reactor in Africa is the proof of what nature can do alone.. so if Pu244 cannot be generated, where does that leaves us for Unbibium 292 and Marinovs claim? exactly!!

He is looking for primordial super-heavy elements that may have survived from the last supernova explosion in the r-process to enrich the solar system at its birth, not ones made on Earth by natural fission or cosmic ray neutrons. Since Sm-146, with a 108 million year half-life has survived from that event, then other 100 million year half-life nuclides will as well.

But without an inert natural carrier (stable samarium) there is no known way for the them to become concentrated to detectable levels, if they exist.

Think about the samarium situation. Stable isotope ratios vary throughout the solar system at the level of a few percent or less.* So any ancient samarium, however far it has decayed today, will still be present in any modern samarium sample, if there is any at all. This is really helpful in finding it.

When looking for new elements, which may exist on Earth at the same quantity, we do not have this convenient concentration and identification mechanism.

*This variation is due to fractionation processes after the early nebula collapsed (and which is thought to have been thoroughly mixed and quite uniform).

also the rocky planet concentrated most of the heavier element and the gas giant capture some of the lightest after the sun ignited.
i would not be surprised to find higher concentration of gold or thorium on mercury than on the mars or titan for example. it might be a small difference though.
Most recent space probe carry along mass spectrometers capable of identifying some isotopes (active or not) it would be very interesting to dig in those results and compare them...

The Volatile Chemist
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Mood: Balancing things out.

Have there been any attempts to produce atoms of 122-126 in colliders?
I'd heard about the natural-122 stuff when I was 13, but back then thought the 'island of stability' was the location at which the isotopes had been found. I note Wikipedia has pages for the theoretical heavy elements, and what methods have been tried to produce them.

My write-ups are on here...
http://www.MeltThe.Ga or http://ptp.x10.mx
doublefocusing
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Radiochem? Love to see it. Shame the readers weren't around when the nuclear chem courses were dismantled at the small colleges.At some point such facilities were deemed politically inappropriate, the planchettes, minature glassware, source kits and all that wonderful old counting equipment went on the scrap pile.If you worked at one of the U's that had a pile, put your sample in the"rabbit"push the button and off it went, to be retrieved later.Really wasn't much of a problem getting accelerator time either. Even the little schools frequently had a Pu-Be source.
Now? with all the wonderful stuff floating around on the net, low level counting looks pretty accessible.Scintillation counters everywhere and a variety of solid state detectors.A neutron generator straightforward to build. Be prepared to develop a good bit of skill with vacuum line tech. Safety? Mostly overblown,but these are the risks of curiousity,
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 Sciencemadness Discussion Board » Special topics » Radiochemistry » Radiochemistry Select A Forum Fundamentals   » Chemistry in General   » Organic Chemistry   » Reagents and Apparatus Acquisition   » Beginnings   » Miscellaneous   » The Wiki Special topics   » Technochemistry   » Energetic Materials   » Biochemistry   » Radiochemistry   » Computational Models and Techniques   » Prepublication   » References Non-chemistry   » Forum Matters   » Legal and Societal Issues   » Whimsy   » Detritus   » The Moderators' Lounge