“ “Ooooooh, preeetty- Stoner
Created by Pro-Teq, Starpath is a sprayable coating of light-absorbing particles that harvests ultra-violet rays from the sun during the day and dramatically lights up like a starry sky at night. The veneer is non-reflective, anti-slip and waterproof, and can be applied to cement, wood, tarmac or other solid surfaces.
Very nice, every car should be painted with this.
I have glow-in-the-dark items all around my house (even glued to the ceiling) and these things glow extremely feebly at best and lose their glow almost completely in about 45 minutes.
I want to see a return to radium (or other radioactive eg. americium) powered night lighting.
mollwollfumble said:
I want to see a return to radium (or other radioactive eg. americium) powered night lighting.
There aren’t issues with providing public access to these materials en-masse?
Why have you got glow in the dark stuff glued to the ceiling?
Divine Angel said:
Why have you got glow in the dark stuff glued to the ceiling?
cause its AWESOME!!!!
:P
Riff-in-Thyme said:
Divine Angel said:
Why have you got glow in the dark stuff glued to the ceiling?
cause its AWESOME!!!!
+1
:)
>Could Sparkling Glow-in-the-Dark Pavement Replace Street Lights?
No. It would probably be bright enough to show you where the path is, but wouldn’t illuminate much else.
I can see this stuff being of most appeal as a new material for graffitists to make a mess with.
I have seen that sort of stuff before and asked some questions about it. Was going to get some for the cactus garden.
I got over glow in the dark stuff fifty years ago.
Peak Warming Man said:
I got over glow in the dark stuff fifty years ago.
very bad sign of being over-ripe human
Tritium
mollwollfumble said:
Very nice, every car should be painted with this.I have glow-in-the-dark items all around my house (even glued to the ceiling) and these things glow extremely feebly at best and lose their glow almost completely in about 45 minutes.
I want to see a return to radium (or other radioactive eg. americium) powered night lighting.
I hate to agree with Wookie, but I think tritium’s a better option.
Beta emitters (like tritium) are preferred for radioluminescence: it’s easier to trigger phosphors with beta particles than alpha particles, and alpha emitters have a tendency to also emit gamma, which degrades the phosphor. There are plenty of old clocks around that used to glow in the dark, but no longer do so, even though their radium-based paint is still more than active enough to set off a Geiger counter.
I have a tritium powered glow-in-the-dark key ring which is about 10 years old, so it’s lost almost half of its “glow power” (the half-life of tritium is 12.32 years), but it’s still easy to see at night.
The energy of the beta particles emitted by tritium averages around 5.7keV, making them much less energetic than the electrons fired at the screen of an old CRT TV or computer monitor (which used acceleration voltages typically around 20 kV, IIRC). However, as with CRT electrons there is some braking radiation production (which can include X-ray) when beta particles decelerate.
Unfortunately, the Americans aren’t happy with tritium being used commercially, since it can be used in thermonuclear devices.
A while ago, I saw a website advertising a new type of tritium glow paint. The tritium and phosphor is encapsulated in tiny beads, so the radiation hazard from it is minimal. But I can’t seem to find it today…
For more info, see http://en.wikipedia.org/wiki/Tritium_illumination
Divine Angel said:
Riff-in-Thyme said:
this seems apt here
Do souls glow in the dark?
if you expose them properly
PM 2Ring said:
mollwollfumble said:
Very nice, every car should be painted with this.I have glow-in-the-dark items all around my house (even glued to the ceiling) and these things glow extremely feebly at best and lose their glow almost completely in about 45 minutes.
I want to see a return to radium (or other radioactive eg. americium) powered night lighting.
> I hate to agree with Wookie, but I think tritium’s a better option. Beta emitters (like tritium) are preferred for radioluminescence: it’s easier to trigger phosphors with beta particles than alpha particles, and alpha emitters have a tendency to also emit gamma, which degrades the phosphor.
Yes, but beta rays are harder to block than alpha rays, which is one of the reasons that smoke alarms use Americium, which is obtained from high level nuclear waste. Where does the tritium come from, dismantled thermonuclear weapons?
> There are plenty of old clocks around that used to glow in the dark, but no longer do so, even though their radium-based paint is still more than active enough to set off a Geiger counter. The energy of the beta particles emitted by tritium averages around 5.7keV, making them much less energetic than the electrons fired at the screen of an old CRT
Noted. I didn’t know that.
PM 2Ring said:
I hate to agree with Wookie, but I think tritium’s a better option. Beta emitters (like tritium) are preferred for radioluminescence: it’s easier to trigger phosphors with beta particles than alpha particles, and alpha emitters have a tendency to also emit gamma, which degrades the phosphor.
mollwollfumble said:
Yes, but beta rays are harder to block than alpha rays, which is one of the reasons that smoke alarms use Americium, which is obtained from high level nuclear waste.
True, beta is harder to block, all else being equal, but low energy beta isn’t that hard to block, and it’s not very dangerous. OTOH, alpha does have another advantage over beta: alpha emission energies tend to fall into a fairly narrow range, whereas beta are emitted over a wide energy range, since the emission energy gets shared between the electron and the antineutrino, and the angle between those two is a random variable.
mollwollfumble said:
Where does the tritium come from, dismantled thermonuclear weapons?
However, as I said earlier, the Americans tend to discourage people from making it these days.
PM 2Ring said:
PM 2Ring said:I hate to agree with Wookie, but I think tritium’s a better option. Beta emitters (like tritium) are preferred for radioluminescence: it’s easier to trigger phosphors with beta particles than alpha particles, and alpha emitters have a tendency to also emit gamma, which degrades the phosphor.mollwollfumble said:
Yes, but beta rays are harder to block than alpha rays, which is one of the reasons that smoke alarms use Americium, which is obtained from high level nuclear waste.True, beta is harder to block, all else being equal, but low energy beta isn’t that hard to block, and it’s not very dangerous. OTOH, alpha does have another advantage over beta: alpha emission energies tend to fall into a fairly narrow range, whereas beta are emitted over a wide energy range, since the emission energy gets shared between the electron and the antineutrino, and the angle between those two is a random variable.
mollwollfumble said:
Where does the tritium come from, dismantled thermonuclear weapons?
That does appear to be a major source. It’s not hard to make – just irradiate some lithium with neutrons by putting it into a fission reactor, eg as a replacement control rod. Preferably Li-6, although you can also make tritium from Li-7, if you have fast neutrons.However, as I said earlier, the Americans tend to discourage people from making it these days.
my take on nuclear power for spacecraft would be using betavoltaics to extract power from decaying tritium or by converting having a tritium light source to a phosphor plate (tritium lighting)
this would be solid state, reliable power for interplanetary spacecraft anything else is whistling in the wind