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Well, since that thread was locked I have to answer here instead. I don't think the technical part we were discussing was the reason for the lock.
W∴ Balboos, GHB wrote: Interestingly - "fine mesh" - can be obtained in more than one way. A single thing sheet of very tightly woven material or many layers of less tightly woven material. The former (fine mesh) will react poorly to pressure increases and redirect to vent said pressure; the latter (if the coarser mesh doesn't get extreme) doesn't have the problem with pressure (by comparison) but does effective trapping of droplets as the wend through the contorted path between mouth and "outside", trapping droplets on the fibers during many collisions.
I thought you might find it interesting that those N95 (Actually N,R,P 95,99,100) masks we read about all the time nowadays are having much larger "mesh" than viruses.
They work by being made made from a nonwoven material with statically charged fibers, and particles are forced to make a lot of turns when following the air stream and are getting stuck on these statically charged fibers.
They also don't lose efficiency when being used a lot, they just get heavier to breathe through.
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Basically an agreement. As for a mesh small enough to trap a virus? It would, for all practical purposes, be impermeable - at least in terms of breathing through it. Virus' are extraordinarily small.
When Louis Pasteur was trying to isolate the rabies virus he found it passed through his finest filters. Virus' are basically large molecular scale entities. Now one doesn't emit virus' on their own (such as during a cough or sneeze) but as content of the droplets - and even the smallest droplet can contain an unaccountably large number of virus' (of various types, concurrently).
Taken to the next smaller level - masks against poison gasses - far smaller than a virus. They rely upon adsorption (such as activated charcoal) and decomposition/reaction, such as (imaginary scenario) trapping chlorine gas with sodium carbonate (going to Nacl (salt) and CO2.
The thing is that to prevent outgoing (masks worn by the public) it may make more sense to target the droplets with (moisture) adsorbent surfaces (threads) in a comparatively free flowing but thick-enough matrix. Easier to get. Easier to wear for longer periods. Easier to clean/reuse. And I'd suspect, more effective.
But you saw what I meant to begin with.
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Is letting the cat out of the bag easier than getting it back in?
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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Don't know, I'd refer to Erwin Schrödinger for this one.
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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If it's a feed-bag, it oat to be easier. There may, however, be claws to exercise caution.
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Fangs for that! 
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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OriginalGriff wrote: getting it back in?
You can only get it in once.
They tend to remember, and don't think twice about letting you know they're unhappy about being placed there in the first place.
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As far as I know you have a cat: why does it even enter your mind to pose the question?
Cats have long memories and don't even consider allowing having bad things done to them again.
After all they do have personnel to take care of them. 
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Is that what you are calling it when you want to get it back in - a cat?
(Actually, I thought that was more like the bag)
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Why did they sack the cat? Sleeping on the job?
If you can't laugh at yourself - ask me and I will do it for you.
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After the success of my first galaxies, the next night I headed out again, new target and tried longer exposures, and pretty much used up the camera battery on the one target taking around 60 x 120s exposures. After stacking them and rejecting some fuzzies, and then tweaking I ended up with what I thought was a reasonable outcome!
M63 Sunflower Galaxy
It never ceases to amaze me at the shear numbers involved in these objects. Millions of lights away, thousands of light years in diameter and containing billions of stars.
One of my pals pointed out that of one of the pictures I caught the first night, when the light photon journey started travelling away from the target, dinosaurs were still on the Earth.  I had never really thought about it like that!
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I wonder how long of a red line you'd get if you took photos of a galaxy where Mars was also in view.
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It reminded me that I miss the APOD.
"Five fruits and vegetables a day? What a joke!
Personally, after the third watermelon, I'm full."
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Sorry I'm not to that standard yet!
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I check it out every day : Astronomy Picture of the Day[^]
"They have a consciousness, they have a life, they have a soul! Damn you! Let the rabbits wear glasses! Save our brothers! Can I get an amen?"
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Wikipedia says, Quote: There is a general lack of large scale continuous spiral structure in visible light, so it is considered a flocculent galaxy.
I guess that's cause the galaxy has so much gas!
The difficult we do right away...
...the impossible takes slightly longer.
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Love these photos, keep posting! My best effort was Jupiter with 3 moons, I'm still impressed every time I look at the 4 white dots on the black background!
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DaveAuld wrote: Sunflower Galaxy
Image the size of the seeds...
Nice picture!
If you can't laugh at yourself - ask me and I will do it for you.
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Hopefully less 'educational' than yesterday. 
Matrix algebra was no help, so he ran online. (9)
Software rusts. Simon Stephenson, ca 1994. So does this signature. me, 2012
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No.
Software rusts. Simon Stephenson, ca 1994. So does this signature. me, 2012
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NON LINEAR?
(Anag of RAN ONLINE, could be Matrix Algebra)
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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