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John Cuthber

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John Cuthber last won the day on November 10 2023

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About John Cuthber

  • Birthday 11/10/1965

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  1. I think you just discovered Kirchhoff's radiation law. https://en.wikipedia.org/wiki/Kirchhoff's_law_of_thermal_radiation
  2. In all sensible probability, nine lives won't be enough.
  3. Do you understand that those classifications are hierarchical? All rosales are rosids All prunus are rosaceae And all of them are plants
  4. With a lot of trouble and care (and a mass spectrometer) you can measure acid base equilibria in the gas phase with no solvent present. Many people have got PhDs by doing this, but I'm not sure it's had much wider use. (By wider, I mean outside the lab) You don't get "H+" ions in water. You get a hydrated version, typically modelled as [H9O4]+ So you are almost always looking at how strong an acid is compared to water. In principle, if you have just liquid ammonia, there are always some protons around to soak up. They arise from ammonia acting as a base. 2 NH3 --> [NH2] - + [NH4]+ The extent of that reaction is tiny, but not zero. (It's about 1 in 10 ^33)
  5. A Post-it note? https://www.staples.co.uk/office-supplies/writing-supplies/correction/post-it-cover-up-and-labelling-tape-25-4mm-658h
  6. No, or at least, only very slightly. More sugar would draw water in from the surrounding tissues (and from the blood) and that would dilute the acid a bit, raising the pH.
  7. Does the universe have a calendar? How did/ does it know when to switch the expansion on and off?
  8. And, if the universe is accelerating away from me, and has been doing so eternally, why is (any of) it still here? The question was "What makes you think the universe was "made up" and hasn't always existed?"
  9. Among other things... https://en.wikipedia.org/wiki/Olbers's_paradox
  10. Every 10 minutes the temperature/ humidity sensor in my garden sends data (by radio) to a display in my house- something like this. https://www.weathershop.co.uk/technoline-ws9130-weather-station (Mine is a different brand) And some device like that is vastly more likely to be the source of the RF which you see than any sort of "attack". If you are experiencing health problems you should consult a doctor.
  11. https://en.wikipedia.org/wiki/Glass-ceramic#Glass_ceramics_in_cooktops And "An interesting property of these glass-ceramics is their thermomechanical durability. Glass-ceramic from the LAS system is a mechanically strong material and can sustain repeated and quick temperature changes up to 800–1000 °C. The dominant crystalline phase of the LAS glass-ceramics, HQ s.s., has a strong negative coefficient of thermal expansion (CTE), keatite-solid solution as still a negative CTE but much higher than HQ s.s. These negative CTEs of the crystalline phase contrasts with the positive CTE of the residual glass. Adjusting the proportion of these phases offers a wide range of possible CTEs in the finished composite. Mostly for today's applications a low or even zero CTE is desired. Also a negative CTE is possible, which means, in contrast to most materials when heated up, such a glass-ceramic contracts. At a certain point, generally between 60% [m/m] and 80% [m/m] crystallinity, the two coefficients balance such that the glass-ceramic as a whole has a thermal expansion coefficient that is very close to zero." from teh same page.
  12. The actual data you need is a Henry's law constant. https://acp.copernicus.org/articles/15/4399/2015/acp-15-4399-2015.pdf then you can calculate how much stuff gets into teh vapour phase from a solution of a given concentration and then you can compare that against the permitted concentrations. Good luck. You might also want to know about these. https://assets.publishing.service.gov.uk/media/5a7ce177e5274a2ae6eeb560/scho0307bmkt-e-e.pdf
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