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TIL: Today I Learned

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Zero-hour contracts should have been been banned long ago, but fat chance of that with Brexit supposedly around the corner.
 
TIL: For the second year in a row, Trump has been nominated for the Nobel Peace Prize. Like last year, this year's nomination has also been exposed as a forgery. :o:o
 
TIL that "Objective Tinnitus" is a thing. Tinnitus is a constant sound, usually a 'ringing' or 'buzzing' that can in severe cases make it difficult to hear or concentrate. In the case of Objective Tinnitus, as opposed to the more common Subjective Tinnitus the cause is a blood flow or other structural noise that can actually be heard by a doctor using a probe inserted into the ear. This has no particular bearing on anything, I just thought it was interesting.
 
I too find that interesting.
 
That is interesting. Mostly useless of course, but still interesting. :)
 
TIL - In 1957 The Nevada Test Site made giant blunderbusses powered by atomic bombs...possibly launching objects into deep space before Sputnik I. (pdf)

And apparently made a Far Side cartoon decades before Gary Larson.

plumbob.jpg
 
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Bugfatty300 said:
TIL - In 1957 The Nevada Test Site made giant blunderbusses powered by atomic bombs...possibly launching objects into deep space before Sputnik I. (pdf)

And apparently made a Far Side cartoon decades before Gary Larson.
Click to expand...

Nuclear blunderbuss story:

Spoiler :
In the early days of nuclear power there was a misunderstanding of what caused power levels to change in a reactor...[pause for technical explanations]

Criticality is the measure of how the reaction rate is changing. In a critical reactor, on average, one neutron produced from a fuel atom fission will go on to induce another fuel atom to fission, creating a sustained chain reaction. If more than one, on average, is doing this than the reactor is supercritical and power levels are rising. The departure from criticality is measured in reactivity units, so a critical reactor is at zero reactivity, and you can make power levels increase by doing something to either add positive reactivity or remove negative reactivity, with the generally most direct access being withdrawal of control rods to remove their negative reactivity.

[end pause]

...anyway, what was misunderstood was that power levels not only respond to reactivity, they respond to the rate of change in reactivity. Since control rods are generally moved by motors that run at a fixed speed no one really noticed that part of the power level change was because of the increased reactivity that was added and part was from the actual process of adding the reactivity. For all (well, almost all) practical purposes it worked out the same anyway.

So, there's this tiny little test reactor, and for maintenance purposes the motors that drive the control rods have been removed. Now they are all spruced up and ready to be put back on. The control rods are fully inserted, so the reactor has a bunch of negative reactivity and is at some minute steady power level where stray environmental neutrons are enough to make up for the fact that far less than one neutron per fission is surviving to cause another. And a guy is tasked with hooking up the drive motors.

He goes to connect one, and the gear teeth don't line up with the ridges on the stem of the control rod. Well, actually they DO line up with the ridges, so the motor can't drop into place. The teeth need to be in the grooves between the ridges. So our guy figures "I'll just grab the stem and give it a little yank so the teeth can mesh."

Now, this reactor is subcritical by a huge margin, with a whole lot of negative reactivity, so moving this control rod and taking out a very little bit of that negative reactivity should not be a problem. However, the yank of the control rod removed that small amount of reactivity very very quickly, creating a very high reactivity addition rate and taking the reactor supercritical. It responded by producing a very high power level in just a handful of neutron life cycles, boiling the coolant to rapidly expanding steam that began expelling the control rod so rapidly that the teeth couldn't engage, creating an even faster reactivity addition rate, etc, etc, etc.

In the end this little test reactor, designed to produce several watts of power, produced some hundreds of kilowatts, perhaps even as much as a megawatt...for a very, very short period of time.

The ejected control rod ended up protruding through the several foot thick concrete roof of the containment building, leading to some consideration of the "nuclear gun."

 
So basically, they turned the control rod into an atomic harpoon?
 
Windows 10 offers a breakdown of storage use -- games, videos, pictures, etc. It's not exactly accurate: it declared that I'm using 0% of my memory for videos, because all of my videos are in a folder on the desktop and are attributed to Desktop instead.
 
Today I learned about the Groom of the Stool, a courtier of an English monarch who was responsible for assisting the king in...uh, well...
 
aimeeandbeatles said:
Today I learned about the Groom of the Stool, a courtier of an English monarch who was responsible for assisting the king in...uh, well...
Click to expand...

The truly hilarious part of that is how in ultra stiff Victorian times they changed it from "stool" to "stole" and pretended it had always been about the king's luxurious robes.
 
It goes on the same line as people saying ‘roach’ because they believe that ‘cock’ actually meant, well, a male reproductive organ.
 
TIL: Energy drinks are considered a public health risk in the Netherlands and as such, advertising for them is banned much like advertising for cigarettes is banned in the US.
 
Commodore said:
TIL: Energy drinks are considered a public health risk in the Netherlands and as such, advertising for them is banned much like advertising for cigarettes is banned in the US.
Click to expand...

To Minors due to people dying from them, excessive consumption
 
aimeeandbeatles said:
Today I learned about the Groom of the Stool, a courtier of an English monarch who was responsible for assisting the king in...uh, well...
Click to expand...
Did you watch that PBS documentary about Royal bedchambers that was on TV last night? The presenter said the Groom of the Stool didn't actually have to do the wiping himself, just hand the King the cloth so he could do it himself.

Although I suspect in the case of Henry VIII they probably did have to do the actual wiping, at least in his later years when there wasn't much he could still do for himself.

Commodore said:
TIL: Energy drinks are considered a public health risk in the Netherlands and as such, advertising for them is banned much like advertising for cigarettes is banned in the US.
Click to expand...
I tried a couple of them... they're awful-tasting.

I think my own caffeine issues started back when I had my home typing business. During the busiest times of the year it wasn't unusual to be up for 30 hours straight, to get everyone's papers done on time. Sometimes I needed something to help me stay awake.
 
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Valka D'Ur said:
Did you watch that PBS documentary about Royal bedchambers that was on TV last night? The presenter said the Groom of the Stool didn't actually have to do the wiping himself, just hand the King the cloth so he could do it himself.

Although I suspect in the case of Henry VIII they probably did have to do the actual wiping, at least in his later years when there wasn't much he could still do for himself.
Click to expand...

No, unfortunately - I don't have a TV anymore and my mother is constantly using the one in the living room, so I don't get much a chance to watch anything anymore.
 
Commodore said:
TIL: Energy drinks are considered a public health risk in the Netherlands and as such, advertising for them is banned much like advertising for cigarettes is banned in the US.
Click to expand...

If so, that must be new.
I've seen advertisement for Red Bull like 2 years ago, and my Dutch colleague just said that she also thinks that it's not true.
But maybe something recent, in Germany we had this discussion too, I think.
 
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