User talk:Double sharp
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"Data not decisive" on most stable isotopes
[edit]By the time I write this, Tc, Sg, Hs have "data not decisive" footnote beside their mass numbers. However, I found that Lr, Lv, Bh, Ts (and possibly Bk) are all less decisive than Hs. I'm not sure what should I do, either removing the footnote in Hs, or add the footnote to these 4(+1?) elements.
Also, do this footnote need to extend to elements beyond Hs, like all elements with overlapping 2σ confidence intervals? (This adds Mc and Mt to the list.)
Thanks! Nucleus hydro elemon (talk) 14:40, 31 July 2024 (UTC)
- @Nucleus hydro elemon: I think 2σ is a good threshold. So yes, feel free to add the footnotes, perhaps with an explanation. :) Double sharp (talk) 14:57, 31 July 2024 (UTC)
- Just realized a problem: when we cite NUBASE2020, do we use the symmetrized half-life (using 286Nh as example, 12±5 s) or the original unsymmetrized half-life (9.5+6.3
−2.7 s)? - Nh is a borderline case, if we use the unsymmetrized 9.5+6.3
−2.7 s, then the 2σ confidence interval of 286Nh doesn't overlap with 285Nh; but if 12±5 s was used instead, they crash. Nucleus hydro elemon (talk) 16:01, 31 July 2024 (UTC)- @Nucleus hydro elemon: I would prefer to use the original unsymmetrised half-life. Double sharp (talk) 05:46, 1 August 2024 (UTC)
- Added for Lr, but I have struggle on other elements (and Hs too) that don't overlap at 1σ, but overlap at 2σ. I'm not sure if the following:
- If the 1σ confidence interval is 9.5+6.3
−2.7, then the 2σ confidence interval should be 9.5+12.6
−5.4
- If the 1σ confidence interval is 9.5+6.3
- is still in the range of WP:CALC. If it doesn't, I will have no idea on how to write these footnotes. Nucleus hydro elemon (talk) 07:36, 2 August 2024 (UTC)
- Just realized a problem: when we cite NUBASE2020, do we use the symmetrized half-life (using 286Nh as example, 12±5 s) or the original unsymmetrized half-life (9.5+6.3
Happy First Edit Day!
[edit]![]() | Happy First Edit Day! Hi Double sharp! On behalf of the Birthday Committee, I'd like to wish you a very happy anniversary of the day you made your first edit and became a Wikipedian! The Herald (Benison) (talk) 02:47, 7 August 2024 (UTC) | ![]() |
Invitation to join the Fifteen Year Society
[edit]![](http://178.128.105.246/content-http-upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Fifteen_Year_Society_userbox.svg/125px-Fifteen_Year_Society_userbox.svg.png)
Dear Double sharp,
I'd like to extend a cordial invitation to you to join the Fifteen Year Society, an informal group for editors who've been participating in the Wikipedia project for fifteen years or more.
Best regards, The Herald (Benison) (talk) 02:48, 7 August 2024 (UTC)
— The Herald (Benison) (talk) 02:48, 7 August 2024 (UTC)
- @The Herald: Thank you! :D Double sharp (talk) 03:20, 7 August 2024 (UTC)
Nomination of Crossed square cupola for deletion
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Production of transuranium nuclides
[edit]I was wondering that, which of 250Cm, 254Cf, 252-255Es can be produced in quantity at least of micrograms? I think 253,254,255Es are available because they can be formed when 252Cf absorbs neutron; for the others, I don't think so. 14.52.231.91 (talk) 01:01, 16 August 2024 (UTC)
- Seems to be just Es-253 and Es-254. Es-255 is shorter-lived...but I'm not sure it has ever been done even for Es-253 and Es-254. Double sharp (talk) 04:38, 16 August 2024 (UTC)
- Thanks! At least we can have confidence with 253Es, as Wikipedia states explicitly that "Einsteinium is the element with the highest atomic number which has been observed in macroscopic quantities in its pure form as einsteinium-253". 14.52.231.91 (talk) 00:46, 19 August 2024 (UTC)
- I think 254Es is also OK because it has been used in the nucleosynthesis of ununennium. As for 255Es, it has even longer half-life than 253Es... 14.52.231.91 (talk) 00:55, 19 August 2024 (UTC)
- Back in that 1985 attempt, less than a microgram of 254Es was actually used – which was probably one of the reasons nobody saw anything. (Another is also probably that back then, the cross-section limit wasn't enough to see anything from 248Cm+48Ca either.)
- I actually have a significant worry that 119 will take a while to come after 120 (which has taken a long time already). That's because with the cross-sections likely to be the way they are, a 249Bk target might very well have significantly decayed by the time the first successful fusion occurs. And using 248Cm+51V gets the penalty of having the odd proton in the projectile instead of the target, while 243Am+54Cr will likely have a smaller cross-section than 249Bk+50Ti and leads to a more neutron-poor ER. But oh well, we've all waited fourteen years and counting for 120 in the first place. :) Double sharp (talk) 04:49, 19 August 2024 (UTC)
- Either 119 or 120 coming first would be OK to me - we would be closer to finally finishing the periodic table up to n + l = 8 :) 14.52.231.91 (talk) 02:27, 20 August 2024 (UTC)
- Haha, yes. The Janet table is great! But what I really want is to see the g-block. Hopefully, after that people will finally universally get group 3 correct (after Y comes Lu and Lr, certainly not asterisks or La-Ac). :) Double sharp (talk) 02:55, 20 August 2024 (UTC)
- G-block would be a lot harder, and it's even worse that the first element with a 5g electron comes much later... 14.52.231.91 (talk) 07:00, 20 August 2024 (UTC)
- Yeah, probably each change of projectile will mean things get one or two orders of magnitude worse. :( Probably already E121 has 5g low enough to participate in chemistry at least. But doing actual chemistry with the expected half-lives and low rate of production seems very far off. Still nobody has done Mt. (Okay, to some extent it's partly that Mt chemistry will probably be like Ir, making it hard to get into solution and also hard to find volatile compounds without using F2.) Double sharp (talk) 10:00, 20 August 2024 (UTC)
- What I also find curious is that only the lightest isotopes of Mt and Rg have been directly synthesized and no new hot fusion reactions have been attempted for those elements. Complex/Rational 13:55, 20 August 2024 (UTC)
- @ComplexRational: Considering the cross-section trend, wouldn't it be easier to fill them in from Mc, just like it's easier to produce Cn as an overshoot product from Fl? Though I have been hungering for 231Pa+48Ca for a while, especially now that 232Th+48Ca has been successful. (And can someone please do 241Am+48Ca already? :D) Double sharp (talk) 14:57, 20 August 2024 (UTC)
- Sadly it seems like no one cares about 231Pa + 48Ca, even the most recent reference about it was from 1981. :(
- On the other hand, 241Am + 48Ca got a recent reference.[1] In there, reactions involving 241Am was even considered to create elements 119~122. :) Nucleus hydro elemon (talk) 16:01, 20 August 2024 (UTC)
- @Nucleus hydro elemon: T_T Thanks for the papers! (Though I'd want to stick to 243Am for going beyond 118, at least at first. I wonder how close we are to the proton drip line in this region...) Double sharp (talk) 16:11, 20 August 2024 (UTC)
- For cross sections, targeting Mc and observing its decay chains would certainly be more feasible based on experimental data. However, indirect synthesis is said not to be optimal for investigation of chemical properties.
- And re below, the KTUY chart that I uploaded some time ago suggests that we are already very near the drip line for odd-Z superheavy elements, but the partial half-lives for alpha/SF are expected to be longer than those for proton emission, so I'm not sure if we'd even know. Complex/Rational 18:50, 20 August 2024 (UTC)
- @ComplexRational: Sure, though Cn and Nh were both investigated through indirect synthesis. So at least it's a possible option when the cross-section is likely to be worse for the lighter elements. :) Thanks for the answer on the drip line! Double sharp (talk) 02:55, 21 August 2024 (UTC)
- @ComplexRational: Considering the cross-section trend, wouldn't it be easier to fill them in from Mc, just like it's easier to produce Cn as an overshoot product from Fl? Though I have been hungering for 231Pa+48Ca for a while, especially now that 232Th+48Ca has been successful. (And can someone please do 241Am+48Ca already? :D) Double sharp (talk) 14:57, 20 August 2024 (UTC)
- What I also find curious is that only the lightest isotopes of Mt and Rg have been directly synthesized and no new hot fusion reactions have been attempted for those elements. Complex/Rational 13:55, 20 August 2024 (UTC)
- Yeah, probably each change of projectile will mean things get one or two orders of magnitude worse. :( Probably already E121 has 5g low enough to participate in chemistry at least. But doing actual chemistry with the expected half-lives and low rate of production seems very far off. Still nobody has done Mt. (Okay, to some extent it's partly that Mt chemistry will probably be like Ir, making it hard to get into solution and also hard to find volatile compounds without using F2.) Double sharp (talk) 10:00, 20 August 2024 (UTC)
- G-block would be a lot harder, and it's even worse that the first element with a 5g electron comes much later... 14.52.231.91 (talk) 07:00, 20 August 2024 (UTC)
- Haha, yes. The Janet table is great! But what I really want is to see the g-block. Hopefully, after that people will finally universally get group 3 correct (after Y comes Lu and Lr, certainly not asterisks or La-Ac). :) Double sharp (talk) 02:55, 20 August 2024 (UTC)
- Either 119 or 120 coming first would be OK to me - we would be closer to finally finishing the periodic table up to n + l = 8 :) 14.52.231.91 (talk) 02:27, 20 August 2024 (UTC)
- @ComplexRational: Double sharp (talk) 10:09, 18 August 2024 (UTC)
References
- ^ Deng, Xiang-Quan; Zhou, Shan-Gui (2023-01-25). "Examination of promising reactions with Am 241 and Cm 244 targets for the synthesis of new superheavy elements within the dinuclear system model with a dynamical potential energy surface". Physical Review C. 107 (1). doi:10.1103/PhysRevC.107.014616. ISSN 2469-9985.
Leep year setting for octal and nonary civilizations
[edit]I've come up with the calendar for civilizations living on Earth that use octal or nonary. I suppose that a week is still 7 days, because the number seems to be base-independent. I will use our seconds for comparison, even though a non-decimal civilization would have defined a second to be something else than 1/86400 of a day.
For people using nonary: Set a leap year in every 49 years, then eliminate one every 1309 years, and add one back every 8009 years.
This will make 1849 leap years out of every 8009 years, so a year would be 31638.39 seconds longer than a multiple of a day. The tropical year is 316319 seconds longer than that, so the difference is 7.39 seconds. A period of 8009 years contains exactly 513379 weeks.
For people using octal, there are two choices. The more natural one would be to set a leap year in every 48 years, then eliminate one every 2008 years. But we have to wait for 16008 years until the weekdays repeat themselves. Another choice with a period of 16008 years is to set a leap year in every 48 years, eliminate one every 1608 years, then add one back every 16008 years.
In either case there will be 3318 leap years out of every 16008 years, so a year would be 506758 seconds longer than a multiple of a day, which is only one second short compared to the tropical year!
In conclusion, the octal calendar wins by accuracy but the nonary one wins by a shorter period of weekdays (for comparison, our decimal calendar has yet lower accuracy but an even shorter weekday period). Still, it's amazing that the orbital period of the Earth can give a calendar in periods of a multiple of centuries which is accurate enough, for people using either decimal, octal or nonary :) 14.52.231.91 (talk) 06:51, 22 August 2024 (UTC)
- By the way, my edit triggered filter 1321 when I tried to post all the paragraphs as a whole. But when I performed the edits in posting just some paragraphs at a time, the edits were OK. 14.52.231.91 (talk) 06:55, 22 August 2024 (UTC)
- It seems that the edits were limited to 1280 characters. (Of course, since I did not mean to do any vandalism, my test stops here.) 14.52.231.91 (talk) 07:03, 22 August 2024 (UTC)
- Very cool! The edit filter may not have appreciated these calendars, but I do! :) Double sharp (talk) 07:56, 22 August 2024 (UTC)
- Thanks! :) 14.52.231.91 (talk) 00:49, 23 August 2024 (UTC)
- Very cool! The edit filter may not have appreciated these calendars, but I do! :) Double sharp (talk) 07:56, 22 August 2024 (UTC)
- It seems that the edits were limited to 1280 characters. (Of course, since I did not mean to do any vandalism, my test stops here.) 14.52.231.91 (talk) 07:03, 22 August 2024 (UTC)
Picture of astatine?
[edit]![](http://178.128.105.246/content-http-upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Astatine-211_in_bismuth_target.jpg/220px-Astatine-211_in_bismuth_target.jpg)
This reference[1] showed their bismuth target that contains 211At after irradiation (Fig. 1). Even better, the license is CC BY 4.0 and thus the picture can be used in Wikipedia. The problem is I'm not sure is the black stuff in that picture is real, visible 211At in nanogram quantities, or is it just burnt bismuth or anything else? If it is indeed real 211At then we might be able to use it in the infobox. :) --Nucleus hydro elemon (talk) 13:49, 24 August 2024 (UTC)
References
- ^ Naka, Sadahiro; Ooe, Kazuhiro; Shirakami, Yoshifumi; Kurimoto, Kenta; Sakai, Toshihiro; Takahashi, Kazuhiro; Toyoshima, Atsushi; Wang, Yang; Haba, Hiromitsu; Kato, Hiroki; Tomiyama, Noriyuki; Watabe, Tadashi (2024-04-15). "Production of [211At]NaAt solution under GMP compliance for investigator-initiated clinical trial". EJNMMI Radiopharmacy and Chemistry. 9 (1). doi:10.1186/s41181-024-00257-z. ISSN 2365-421X. PMC 11018728. PMID 38619655.
- @Nucleus hydro elemon: I hate to give this answer, but it's just physically implausible that you're seeing At in any visible quantity. Still, it could be a good picture to illustrate astatine production, just not in the infobox. :) Double sharp (talk) 14:17, 24 August 2024 (UTC)