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Cake day: June 15th, 2023

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  • Other commenters have pointed out the problems with overloading of connectors and reduced efficiency because of the added resistance but there is another really important reason not to chain power strips: circuit breakers work best against short circuits when the resistance between the breaker and the short is fairly low (for instance less than 0.5Ω) so that the current will quickly go over the rated current of the breaker. If the resistance is a lot higher because you have too many extensions between the breaker and the fault, the time the breaker needs to react will go up. Counterintuitively this usually means more energy will be turned to heat by the fault.

    In extreme cases this can mean the difference between a broken power strip that you can just throw out and a burned down house.


  • user134450@feddit.detoCoffee@lemmy.worldDescaling liquid
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    4 months ago

    If you want to be super exact about it it would be roughly 4 times the mass of limescale + mass of already dissolved CaCO3 in your tap water (you can look that up if you know the hardness index of your water).

    But really just don’t be stingy with citric acid and it will be fine is what i am saying.

    Here is the math:

    Spoiler

    2 frac {210.14 g/mol } {100.0869 g/mol} approx 4.2

    <math xmlns=“http://www.w3.org/1998/Math/MathML” display=“block”> <semantics> <mrow> <mn>2</mn> <mrow> <mfrac> <mrow> <mn>210.14</mn> <mrow> <mi>g</mi> <mo stretchy=“false”>/</mo> <mi mathvariant=“italic”>mol</mi> </mrow> </mrow> <mrow> <mn>100.0869</mn> <mrow> <mi>g</mi> <mo stretchy=“false”>/</mo> <mi mathvariant=“italic”>mol</mi> </mrow> </mrow> </mfrac> <mo stretchy=“false”>≈</mo> <mn>4.2</mn> </mrow> </mrow> <annotation encoding=“StarMath 5.0”>2 frac {210.14 g/mol } {100.0869 g/mol} approx 4.2</annotation> </semantics> </math>


  • user134450@feddit.detoCoffee@lemmy.worldDescaling liquid
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    4 months ago

    Note that citric acid works a bit more nuanced than many other descalers: it acts as a chelating agent at high concentrations (2x the Ca2+ concentration) and is more effective at removing scale because of this effect, but at lower concentrations the effect might actually be reversed because it can form solid calcium citrate, which has a very low solubility in water.

    If you are using citric acid based descaler you should make sure that you are always using enough of it to avoid the formation of calcium citrate.









  • user134450@feddit.detoCollapse@lemmy.mlThe Protein Problem
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    6 months ago

    ”nitrogen-rich fossil fuels that feed our culture“ wow this article is really badly researched. the problem is of course real and has been described very well by William Crookes in 1898. The answer back then was the development of the Haber-Bosch process. The input was originally hydrogen from coal not natural gas which shows that the process is a bit more adaptable than this article makes us believe.

    hydrogen can be obtained from many sources (including as a pure substance from wells as white hydrogen) and the reason why we use natural gas today is because it is much cheaper than the alternatives, not because other source materials would not scale as well.

    how we will be creating inorganic nitrogen fertilizer in the future is a question to be solved but it is not an insurmountable problem – more like an upcoming shift in our economic practice because we will have to switch to more expensive sources.



  • instead of putting a grub config in /boot/grub you could also try embedding it directly with grub-mkimage. you would need to point to the grub config that you have with -c and add all the needed modules as extra arguments at the end.

    it is possible that the grub image you installed is just not looking for the config file at the right place.

    or maybe try putting the grub.cfg in the same directory as the grubx64.efi