The h Bar

1:00 AM

We could use some help on this one if someone knows a bit about protein folding:

2

Q: Can AlphaFold predict protein structures around metals well?

(1) Commonly, the metal is at the active site which needs the most prediction precision. (2) Typically, there is only one (or a few) metals in a protein, which contains far more other atoms. So, the structural data that could be used to train AlphaFold could contain far less information about the...

Prateek Mourya

2:59 AM

I am not clear with joules mechanical equivalent of heat please suggest me a good source which can tell which type of energy really converts to heat

Physics Meta

7:27 AM

0

Q: Why Coloured parts of questions are removed?

Out of curiosity, after I learnt the use of mathjax if I thought necessary( obviously may be not for others) I use the colour code to mark any point of my question, but some users suggest edits or reputed users usually remove it by editing it! I am not sure why this happens? Is it a regulation? O...

discussion support

Physics Meta

10:24 AM

0

Q: Can I answer resource recommendation questions by answer it directly?

For example, question Q care about problem A and need some material about problem A, can I answer the question by solve problem A directly?

support

123

11:29 AM

Hi All

skullpatrol

3:50 PM

COUNTDOWN TO WINTERBASH 2020 don't let coV dampen your spirit

6

JMac

4:10 PM

@JohnRennie This seems like it might be something you know about. Is there any reason that water should be more prone to bubbling up when it's colder?

John Rennie

"Bubbling up" ?

You mean when your pour water whether it entrains air to form bubbles?

Or the way standing water in containers forms small bubbles on the surface of the container?

JMac

I have a practical example I'm basing this off of. I have a "water pipe" that I usually leave in my shed. If it was cold over the day and I go to use my water pipe at night, it seems like it's more prone to have excessive bubbling, to the point that the water can bubble through the pipe.

And into the mouthpiece

John Rennie

Ah, a hookah?

JMac

Bong would be the right term (thankfully in Canada they aren't "for tobacco only" anymore)

But the same idea without just a mouthpiece on it instead of a hose

Actually I think it applies to hookahs the same. I feel like I had that happen with a cold hookah before too

John Rennie

I can't think of a reason. The viscosity of water increases with decreasing temperature so it could be a viscosity effect. Apart from this pure water doesn't have any tendency to bubble more at low temperature. If some surface active impurity has got in then it might well be temperature sensitive. A lot of surfactants are quite temperature sensitive.

@JMac I grew up in the Sudan where hookahs were routinely used, so I'm used to that name. I always associate the term "bong" with hippies :-)

Nihar Karve

4:19 PM

@JMac Hear, hear.

@JohnRennie Sudan? Wow, what was it like growing up there?

John Rennie

Europeans lived a privileged life there, so for me as a European child it was great. I'm not sure life was so great for your average Sudanese citizen.

We had to leave in something of a hurry when there was a coup and a fundamentalist government took over. And that was pretty much it for Sudan as a decent place for anyone to live.

It's now a basket case of a country.

JMac

@JohnRennie Ah okay. This could be it actually. The water gets dirty pretty quickly, so it wouldn't surprise me if something it picked up had to do with it. And yeah I'm just used to differentiating bong and hookah, because if you got the two confused you might get a bit more relaxed than you expected lol

Nihar Karve

@JohnRennie technically two countries now

ACuriousMind

@JMac until this point I was trying very hard to figure out why you'd use the "water pipe at night" :D

John Rennie

@NiharKarve Both of them basket cases, though (North) Sudan has recently kicked out a particularly villainous leader so maybe there is hope.

South Sudan discovered the only thing unifying it was killing North Sudanese, and as soon as they got independence they started killing each other instead.

Transcript for