2年前

Ultra-white ceramic cools buildings with record-high 99.6% reflectivity

newatlas.com Ultra-white ceramic cools buildings with record-high 99.6% reflectivity

Scientists in Hong Kong have demonstrated a new ultra-white ceramic material that can drastically cool buildings by reflecting sunlight and heat at record highs. The beetle-inspired material gets its ability from its nanostructure, stays tough to the elements and should be relatively easy to scale…

Ultra-white ceramic cools buildings with record-high 99.6% reflectivity::undefined

Hacker News @derp.foo

Ultra-white ceramic cools buildings with record-high 99.6% reflectivity

newatlas.com /materials/ultra-white-ceramic-cools-buildings-record-high-reflectivity/

14 2

您正在查看单个线程.

85 留言

NightAHawkinLight on youtube has been working on something similar. same kind of snow-like nanostructure to reflect light away, but with the added benefit of a paint that emits light in a wavelength that travels through the atmosphere without interacting with any of it.
so if you point a painted tile at the sky it will actually cool below ambient temperature, it's pretty wild https://www.youtube.com/watch?v=N3bJnKmeNJY
- Tech Ingredients did a video about it as well. https://www.youtube.com/watch?v=dNs_kNilSjk
  The biggest problem with making stuff white and using fancy materials is the amount of crap they get exposed to.
  Moisture is one issue, both in the form of water vapor / condensation as well as rain. But there's also smallish animals, like birds and cats that crawl around on roofs. Not to mention all the insects. Then there is the normal sand and dust in the air, plus all the pollution. Depending on where you live, white stuff gets really dirty within weeks or months.
  I work in a white office building and they have it cleaned with pressure washers twice a year, it takes a whole climbing team a good two weeks to clean the whole thing and it looks dirty again after a few months. And that's just a white form of plastic (HPL) you can blast away on, without causing damage. With these fancy meta materials often they are really fragile and any damage undoes the special properties.
  
  Here is an alternative Piped link(s):
  https://www.piped.video/watch?v=dNs_kNilSjk
  Piped is a privacy-respecting open-source alternative frontend to YouTube.
  I'm open-source; check me out at GitHub.
  
  They could just put a layer of something like Teflon over it. That's why crosswalk stripes feel so slick.
  
  If you put something over it, it loses it's reflective properties. Something is only as reflective as it's upper most layer. Unless you use something transparent, but even things we would commonly think of as transparent usually are only transparent at specific wavelength. And even then it's probably not really transparent, more like translucent. Not to mention things like internal reflections and wavelength lengthening.
  This is a super complex subject with many people all over the world working on it and lots of money being put into it. It likely everything people can think of has been thought of and we need some real effort to get to a workable solution. Since no commercial application has been found, it's not certain this is a fixable problem.
  Too often we see innovative ideas and they are marketed as this is just the first version. We can work out the kinks, extrapolate and get to something real special. In reality this is often not the case, actual limitations apply and not all problems are fixable.
  
  Those are slick from the added glass powder for reflectivity.
  Who’s putting Teflon on road stripes…?
  
  Huh, I stand corrected. I could have sworn I read an article linked in a discussion about solar panel roads that said Teflon was mixed in the paint to keep the stripes from getting dirty super fast.
- Here is an alternative Piped link(s):
  https://www.piped.video/watch?v=N3bJnKmeNJY
  Piped is a privacy-respecting open-source alternative frontend to YouTube.
  I'm open-source; check me out at GitHub.

85 留言