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https://en.wikipedia.org/wiki/Huf_Haus Construction of a Huf Haus in the UK featured in the 2004 series of Grand Designs.

Those are awesome, does anyone export this to the states? We just got a prefab studio from Schildr that's manufactured in Turkey and disassembles into a sea container. I imagine something similar would work for Huff houses?

https://schildr.com/en/@schildrusa


In this context energy=wavelength=frequency, and hard x-rays means x-ray with energies > approx. 5 keV. I am assuming properties they are after in their particular context are <i>tunable</i> hard x-rays with with relatively narrow bandwidth, such that they can tune the energy/frequency/wavelength of their beam to be above the absorption edge of particular elements in the pigments in paintings and compare the x-ray fluorescence maps above and below the absorption so they can see where particular pigments are and thus paintings hidden below the visible painting.

One big advantage synchrotrons have is flux over a broad spectrum. When you want monochromatic x-rays you can start with broad spectrum x-rays from a synchrotron source and throw almost all of the photons away, and still have orders of magnitude more x-rays in your 1 eV bandpass beam than the flux of a laboratory source, (even if it has a peak in its spectrum at the energy you want). The plots on slides 4-6 linked in the first comment [1] demonstrate this clearly.

However, the energy range where inverse compton scattering sources seem most attractive are at energies >100 keV where it appears there is the potential for inverse compton sources to approach and even outperform synchrotron bend-magnet sources (slides 31 to 35), particularly in comparison to bend-magnets/wigglers at synchrotrons with lower storage ring energy than facilities like ESRF (6 GeV). High flux at higher energies (>100 keV) is difficult to generate at the more common 2.0-3.0 GeV storage rings.

[1] https://indico.cern.ch/event/1088510/contributions/4577523/a...


Lots of interesting experiments with solar collection here: https://www.youtube.com/@sergiyyurko8668/videos


Whaoo, super interesting, thanks for the link.

Some of their projects follow the same idea of a grid of small square mirrors.

However, they choose to put the mirrors on the ground (which is simpler) and move the target at the focal point (which is not simpler).

Good source of inspiration, I will watch their videos.


Including one of the hardest of them all: https://en.wikipedia.org/wiki/Allocasuarina_luehmannii


McMaster-Carr seems to have done it OK


I have progressed from Dokuwiki -> Tiddlywiki -> Gollum. I can now write everything in asciidoc.


The core itself (Xtensa) is from a US company, Tensilica.

https://en.wikipedia.org/wiki/Tensilica


Interesting - I always wondered what happened to Tensilica.

They seemed ahead of the game in manycore, but manycore doesn't seem to have panned out.



This appears to be a really nice series of articles, but wow, what an annoying format. Just give me a .PDF or single .html page, don't make me click 'Next' thirty times. :(

He's not even doing that to show ads. He's just doing it because, hey, it's not like he wants to read it.


I've been using his arduino PID library to stabilize a camera platform and the library works pretty well.


Radioactivity of rocks is caused by only a few elements so is useful to consider the minerals in which those elements are hosted. i.e. the radioactivity is not evenly distributed among the minerals that comprise granite. The elements that contribute most to the radioactivity of granite are U, Th and K. The K is mostly contained in alkali feldspar and mica. The U and Th are contained in accessory minerals, such as monazite and zircon. Monazite and zircon are dense, robust minerals, which means they persist after weathering and go on to accumulate in detrital sediments, and we call the sediments in which they are concentrated heavy mineral sands. Alkali feldspar is much less robust and rarely survives in mature sediments (i.e. quartz-rich sands), instead all the K ends up in clays.

When heavy mineral sands are processed to extract the Ti and Zr ( from rutile, illmenite, zircon), the residual concentrate is rich in monazite. This material comprises the bulk of our easily accessible Th reserves. However, you can't just leave this monazite-rich material lying around heaps, as it creates a windborne radioactive dust hazard, so it gets mixed back in with the other light material. This is a bit of a shame. All that energy and effort is expended to extract the heavy minerals, but as there is no immediate market for the monazite, and it is a liability to keep it in the extracted state, all that work hard work is undone to mitigate the dust hazard and it gets mixed back with the quartz etc.

So it is perhaps somewhat ironic that we mine beaches to get the minerals that are the source of the bulk of the radioactivity of granites.



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