The h Bar - 2019-07-25 (page 1 of 2)

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1:30 AM

How 5G Cell Service Could Hurt Weather Forecasts

Well this is very concerning...

danielunderwood

I don't think that's an issue where I live. Just replace the forecast with "hot with an entirely random 10% chance of rain" and we're good to go

6 hours later…

7:28 AM

morning

morning

morning

I wonder if there's any famous scientist on vixra

Vixra?

Arxiv without peer review

A nest of cranks

In the Norton's dome solution, why is there a factor of 1/144?

Oh wait

I just got it

nvm

It's $12^2$

There's some question on PSE about the difference between initial value problem and boundary value problem for the Lagrangian

which makes me think

I should read again on the van Vleck determinant

since it's basically the Jacobian between the two

7:44 AM

hmm

van Vleck determinant is one of Those Things

The important-ish physics thing nobody talks about

is this all to me @Slereah ?

No

More of an all around statement

to be enjoyed by all

8:11 AM

I gave a negative answer to this question that asks if there's a DC form of light. I believe my answer to be correct as far as it goes, but one of the other answerers isn't too happy with it. I'd appreciate some feedback from people who know more about quantum optics, especially @EmilioPisanty ...

@PM2Ring your answer looks fine to me, but I'm not sure it's an answer to the question since the question doesn't make sense. I don't think user47014 is making a useful point since current is not the same as the motion of the electron de Broglie wave.

The de Broglie waves of the electrons in a conductor have very high velocities. The current is due to an average velocity so it isn't a property of any single electron.

8:29 AM

I wonder how many people pronounce De Broglie correctly

@PM2Ring I don't get the question at all and I'm surprised it has 4 answers

Dee Brrray

8:54 AM

@Slereah Well I'm starting to question the reliability of my dictionary

user image

for reference

user image

@SirCumference that's correct, at least

@Secret De Brogley

Novalium Company

@SirCumference Beff Jezos #beefjesus

mathnet.ru/links/bca4d77157a7954265fa06e30bc48edd/rm7876.pdf

Oh no

@SirCumference Thick accent, perhaps

The Father, the Son, and the Howwwwly gawst

@Slereah Welp it's based on Oxford English Dictionary

lexico.com/en/definition/de_broglie,_louis-victor

Wikipedia definitely says its pronounced differently

9:01 AM

That page actually gives the wrong and the correct pronounciation

/də bʀɔj/

maybe the wrong one is widespread enough to be listed

@Slereah It definitely is. Plenty of people I know say something that sounds more like a slurred "de broccoli" :P

heh

Novalium Company

Beff JEZOS

Oh no

To complete my page on homogeneous cosmology, I have to deal with the Cauchy problem for the Laplace equation

turns out things are very bad for the Laplace equation

9:37 AM

Hello

I looking for some reference on CFT correlators at finite temperature. Any suggestions ?

Novalium Company

@user91411 try ebay

Did you check Di Francesco

Novalium Company

Guys, how to determine how much funds someone would need for a prototype of a project?

Do I just go around amazon and see how much individual parts cost or?

^ (I think that would be a pretty good estimate)

1 hour later…

10:47 AM

It would be a good start yes

11:06 AM

Turns out the real EoM for a relativistic point particle is $$\left[ - \frac{\ddot{x}^\mu(\tau) \dot{x}_\mu(\tau)}{(\dot{x}^\mu(\tau) \dot{x}_\mu(\tau))} \dot{x}_\mu(\tau) + \ddot{x}_\mu(\tau) \right] = 0$$

This one being indeed invariant under reparametrization

11:19 AM

30° now in Chester and still climbing

@JohnRennie Would be nice if it were that cool here

Luckily I'm always cool (ignore anything my teenage relatives might have to say on this subject)

I really took the wrong two days off to get some shopping done :P

My one unavoidable task for today is getting a haircut, which shouldn't be too arduous since the hairdresser is 5 minutes walk from my house. After that I propose to drink cold beer and watch videos of cats on YouTube.

@JohnRennie Wow mister Rennie, you're not an old fuddy duddy at all

Do you bring your acoustic guitar at the youth gatherings to play some rock and roll music

Jam with the kids

11:30 AM

One advantage of starting at 5 a.m. is I managed to get some work done before it got too hot to think, though admittedly that work consisted mostly of realising all the code I wrote yesterday has to be scrapped and rewritten.

@Slereah I don't have a guitar so I bring my collection of Emerson, Lake and Palmer CDs.

Mithrandir24601

@JohnRennie yeah, similar here. I'm actually wearing shorts today, which only come out when it's at least 30°

I am in shorts and sandals today

But alas I'm afraid I will still fry

41°C at its peak

41° wow!

wow, the weather here is actually relatively cool today, calling for a high of 26°C

I'm afraid today I die

It was nice knowing you

12:06 PM

Hm

How does time translation invariance work, at the action level

Do the boundaries move or not

If I have $$S[x(t), t] = \int_{t_a}^{t_b} L(x(t), t) dt$$

With the new time coordinate $t' = t + T$

Is the new action $$S[x(t'), t'] = \int_{t'_a-T}^{t'_b-T} L(x(t'), t') dt'$$

or $$S[x(t'), t'] = \int_{t'_a}^{t'_b} L(x(t'), t') dt'$$

People always just do it using infinitesimal time translations but bugger that

I think it should be the second one, because otherwise the first one is true by definition?

In which case it doesn't allow for Lagrangians that aren't time translation invariant

12:24 PM

user image

whoa

15

Q: A question's sidebar stats are now under the title, why?

Very recently, past few minutes or so?, a new build was pushed out that changed the location of a question's stats from the top of the sidebar content to underneath the title. I can't exactly put my finger on why this change feels odd. Perhaps it is because statistical information like that be...

support design sidebar

4

A: Display post asked/viewed/active info directly beneath the question on mobile

This seems to be live as of now. The sidebar widget has been removed and the 'Asked', 'Active' (if applicable) and 'Viewed' information is now directly beneath the question on all screen sizes. This is how the current question looks like:

2

A: Helpful sidebar content is down below

Put asked/viewed/active stats under the title, with subtle formatting. This seems to have been addressed in the latest build. This is how the current question looks like right now:

It is so much more intuitive this way

It looks too prominent to me

but I suspect I'll get used to it fairly quickly

12:39 PM

I prefer too prominent over "glaze right over it when looking for it" as I've had happen to me with the old layout

I think it was because most of the other information along the sidebar is only tangential to the question, so I wasn't looking towards the sidebar for direct question information

@JMac "glaze right over it when looking for it" is gonna happen regardless of how prominent it is

courses.physics.ucsd.edu/2010/Fall/physics200a/LECTURES/…

this seems relevent

@Slereah what's relevent?

to what I am doing

Keep up

@EmilioPisanty That's true, but it's in a much more intuitive place now, with the rest of the question information instead of with the rest of the other site/network information

12:45 PM

@Slereah no, as in, what does "relevent" mean? =P =P =P

@ACuriousMind It's basically this: Light is a wave, and AC current is also a wave. But there's also DC current, so is there a DC form of light? The first 2 answers were posted before the OP responded to my comment, clarifying that they are not asking about the light from a bulb powered by AC or DC current.

@EmilioPisanty it's a rel event

obviously

Annoyingly, the view count is still invisible in the mobile view. But that's a minor annoyance, compared to the inability to improve impending edit on a mobile device.

@Slereah ah, gotcha

don't sass me boy

2

12:52 PM

ain't no sass here

1:07 PM

Hm

I think I have the Clue

\begin{eqnarray}
\dot{x}(t + T) = \dot{x}(t) + \sum \frac{T^n}{n!} x^{(n)}(t)
\end{eqnarray}

so that $$S[t + T] = \int \dot{x}^2 + 2 \dot{x} \sum \frac{T^n}{n!} x^{(n)}(t) + (\sum \frac{T^n}{n!} x^{(n)}(t) )^2$$

But $$\frac{d}{dt}(\dot{x} x^{(n-1)}) = \dot{x} x^{(n)} + \ddot{x} x^{(n-1)}$$

By recursion we can express every term of the form $\dot{x} x^{(n)}$ as a sum of total derivatives

Although...

What of the third term

hm

$$\frac{d}{dt}(\frac{1}{2}\dot{x} \dot{x}) = \dot{x} \ddot{x}$$

$$\frac{d}{dt} (\dot{x} \ddot{x}) = \ddot{x}^2 + \dot{x} \dddot{x}$$

Hm

Don't think you can express $\ddot{x}^2$ as a total derivative, can you

On the other hand, it is part of the third term

Agh

I should do that at home

Novalium Company

1:44 PM

Why aren't there consumer available e-paper capsules? Just like there are individual LEDs instead of LED displays (or LCD).

For example, one capsule is $1cm^3$ and has the smaller black/white electrically charged balls.

@NovaliumCompany What would the consumer do with them?

Novalium Company

@ACuriousMind What the consumer does with LEDs donno

LEDs are bought by all sorts of electronics hobbyists

But I don't see what sort of hobbyist would have use for a single e-ink capsule

Novalium Company

What sort of use do they have for LEDs?

What they do with LEDs, they'll do with the capsules

You can wire them up to circuit boards you've built, connect them to something like a raspberry pi as status indicators or just to have pretty lights...

Novalium Company

1:50 PM

Well, you'll have pretty reflectors, also you can use them as indicators.

A single capsule doesn't do anything

Novalium Company

A single LED also doesn't, in that logic

An LED you can just stick into a circuit - literally connecting two wires - it's not quite so easy to use a capsule

Novalium Company

Why not?

You just charge the both electrode plates and the balls go to their positions. Reverse the signs, the balls reverse positions, simple

What are the balls in the capsule made of anyways? How are they charged? What is the fluid in the capsule?

@NovaliumCompany So you need electrode plates and some way to control the field from these electrodes and a way to hold the capsule in place..i.e. you're essentially just rebuilding a small e-paper display

Seems a bit pointless when you could just buy the display directly.

Novalium Company

1:55 PM

Pff you're right :P

@NovaliumCompany Not all are the same, but titanium oxide particles (white) suspended in any black-dyed fluid will do

Novalium Company

You mean titanium dioxide?

Example of a black-dyed fluid?

And also, in the red, white, black display, what are those red capsules?

@NovaliumCompany Huh? I mean you take any fluid that's convenient for you and dye it black.

Novalium Company

@ACuriousMind Tap Water in black paint?

for instance

Novalium Company

2:02 PM

Is titanium dioxide defaulty charged?

That's...not a meaningful question :P

Novalium Company

Why does it get attracted to the electrode plates?

It's like a magnet?

Well, they did something to charge the t.o. when they put it in the capsule

Novalium Company

So if I buy directly t.o, it won't work?

What methods did they use?

No idea, but there are many ways to generate charge - you just need to be careful that the particles don't discharge by coming in contact with a conductor before you seal the capsule

Novalium Company

2:05 PM

Can I buy charged $TiO_2$?

there's probably nothing special about the titanium dioxide w.r.t. this process - it's chosen for its white color

No idea, but I would be very surprised. It's rather annoying to store charged objects so that they keep their charge, but it is not difficult to generate charge when you need it

Novalium Company

What method can I use in home to charge the t.o?

Well, one way familiar to all students of physics would be a van Graff generator, but why'd you want to do that

Novalium Company

Ok, if I was to make a single capsule (about $cm^3$ in size) in home, what would be the best way to do it?

No idea. Given that I'm not in the business of producing ink capsules, I have no idea what's actually practical

Novalium Company

2:13 PM

Alright, if I buy t.o, I'll have to charge it in some way right? Will the van Graff generator method be suitable for such substance?

Why not try to calculate that yourself?

It's really not difficult to charge something that's not a complete isolator: You just need to touch it to something that's charged.

The difficult part is not discharging it again while you handle it.

Novalium Company

@ACuriousMind Got it, thanks!

So I'll charge aluminium foil and put the t.o over it, then remove the aluminium foil and be careful the t.o doesn't touch anything conductive?

So the t.o is a conductor?

wait

how will I go about charging the aluminium foil xDD

Again, I can't give you any specific instructions.

Novalium Company

touching it to a battery for a few seconds?

Can I rub the t.o in my hair xD

2:18 PM

(and I don't understand why you're so intent on producing a capsule yourself, but that's another matter :P)

Novalium Company

@ACuriousMind No problem. Thanks for all the information

This is a random conversation

0

Q: Why did post information move to below the question title?

I am not complaining about this, but just wondering why the data about a question's asked time, last active time, and view numbers has been moved from the right side of the question to underneath the question title on the desktop version of the site. (I think this is a recent change? I just notic...

discussion site-enhancement

I'm a bit surprised but also amused that SE's filters let the question What is "ass door"? on HNQ.

Hm, wait

2:26 PM

no time to wait!

If an action has a Lagrangian that doesn't depend explicitely on time

Is it always by default time translation invariant

bentnib.org/conservation-laws.pdf

@ACuriousMind I'm just waiting for the twitter thread that gets ELU banned from HNQ

^this paper seems to imply that the action becomes $$\int_a^b L(t + T, q(t), \dot{q}(t)) dt$$

After all the proper variable changes

@Slereah yes

Ah, that would certainly make things simpler

2:27 PM

We've just had a brief thunderstorm and it has dropped the temperature by 5°. Were I stereotypically English I could get fascinated by the weather.

it's still 39°C over here, rain is only predicted for Saturday

I'm not 100% sure why the time-translated action becomes $$\int_{\Phi(a)}^{\Phi(b)} L(q(\Phi^{-1}(t)), \frac{d}{dt}q(\Phi^{-1}(t))) dt$$

But it's a start at least

2:42 PM

@SirCumference There is always a bigger fish: meta.stackoverflow.com/q/387546/4064062

Novalium Company

2:58 PM

In the e-paper display,where are the wires coming out from the top of the display? (so an electric field can be created)

are they microscopic and very tiny so they are invisible to the eye?

What?

Novalium Company

You know, from the top and bottom electrodes, there must be wires coming out right?

You mean the "top transparent electrode"?

Novalium Company

Yes

I'd imagine those wires are from the same material as the transparent electrode, hence transparent :P

Novalium Company

3:01 PM

wooow

The "wires' are the transparent electrode, no?

Novalium Company

user image

meh?

Where can I buy transparent electrode layer and transparent wires?

Have you tried asking Google that? :P

Novalium Company

google.com/…

and no such thing as transparent wires exist

I tried asking google yes :D

I can't find "transparent electrode layer" anywhere, help :p

When I google "buy transparent electrode" I get plenty of hits

Novalium Company

3:11 PM

any cheaper alternative?

The material commonly used for transparent electrodes in LCDs is tin oxide.

Also Indium tin oxide

Indium tin oxide

Indium tin oxide (ITO) is a ternary composition of indium, tin and oxygen in varying proportions. Depending on the oxygen content, it can either be described as a ceramic or alloy. Indium tin oxide is typically encountered as an oxygen-saturated composition with a formulation of 74% In, 18% O2, and 8% Sn by weight. Oxygen-saturated compositions are so typical, that unsaturated compositions are termed oxygen-deficient ITO. It is transparent and colorless in thin layers, while in bulk form it is yellowish to grey. In the infrared region of the spectrum it acts as a metal-like mirror. Indium tin oxide...

Novalium Company

Is there any alternative cheaper way to make the top transparent electrode?

Maybe making the sides of a normal electrode (+) and the bottom (-)?

Also, the TiO2 shouldn't dissolve in the black-dyed water right?

Tin is pretty cheap. But I guess making large transparent crystals of it isn't easy for an amateur to do.

@NovaliumCompany Right. Titanium dioxide is insoluble in plain cold water. You need stuff like hot sulfuric acid.

Novalium Company

3:27 PM

Indium tin oxide glass is a transparent electrode layer?

@PM2Ring Great!

@NovaliumCompany The indium tin oxide is a conductive layer deposited onto the glass. You basically condense the vapour onto the glass surface.

Novalium Company

Also, I'd have to cut the transparent electrode layer into smaller pieces and glue a wire to each one? (to make the electric field)

Glue? Glues tend to be insulators. Wires need to be soldered or welded to conductors. You probably should learn a bit about vacuum deposition.

Vacuum deposition

Vacuum deposition is a family of processes used to deposit layers of material atom-by-atom or molecule-by-molecule on a solid surface. These processes operate at pressures well below atmospheric pressure (i.e., vacuum). The deposited layers can range from a thickness of one atom up to millimeters, forming freestanding structures. Multiple layers of different materials can be used, for example to form optical coatings. The process can be qualified based on the vapor source; physical vapor deposition uses a liquid or solid source and chemical vapor deposition uses a chemical vapor. == Description... ==

That article is just a very brief intro to this family of very important industrial processes which are vital to many facets of modern technology.

Novalium Company

@PM2Ring I know that wires are soldered, I was just using the term "glue" for fun. I have a soldering station on my desk :D

@PM2Ring Thanks, will read

3:43 PM

@NovaliumCompany Oh, ok. I learned to solder when I was 10. I don't do much soldering these days, so my technique isn't fantastic, but I can do a decent job when I need to... most of the time. :) OTOH, my step-dad was an electronics technician, and even though he retired over 10 years ago, he is still a true artist with a soldering iron.

Novalium Company

@PM2Ring Cool :-)

time for a doner kebab brb

Are there any other alternatives to a transparent conductor layer that I can find somewhere in home? Maybe from an old phone?

@ACuriousMind is there a canonical way of searching for translations from German of old papers? Although I'm looking for a general answer the specific paper I have in mind is link.springer.com/content/pdf/10.1007/BF01445847.pdf. My German is good enough for me to read with at an unhurried pace but I have to share this with less versatile speakers...

@ZeroTheHero I don't know of any

rats...

ok thanks for the feedback.

Novalium Company

@PM2Ring So yes?

Guys, is TiO2 dangerous in any way? I don't want burning my house down

3:59 PM

it's toxic

@ZeroTheHero google the title + translation

Novalium Company

@ACuriousMind the fuck?

I just ordered some

meaning, I shouldn't eat it?

@ACuriousMind Are you sarcastic?

TiO2 is in bread and gum

When it comes to your safety, you should rely on better sources than a random internet guy!

Novalium Company

@ACuriousMind True, I'll google

"The toxicity of titanium dioxide appears to be low." - Google 2019

I'll not eat it and avoid smelling it.

Titanium dioxide in its normal form is mostly safe, since it's so insoluble and quite stable & unreactive. But there is some concern over the use of TiO2 nanoparticles, especially when inhaled. See en.wikipedia.org/wiki/Titanium_dioxide#Health_and_safety

Novalium Company

4:07 PM

What is nanoparticles?

I ordered in powder form

@NovaliumCompany Seriously? You can Google that. Please don't expect people in this room to spoon-feed you knowledge. Otherwise, you will be perceived as a help vampire.

Novalium Company

@PM2Ring Right, sorry

Novalium Company

4:32 PM

nvm, I googled :)

@JohnRennie Hi

@Abcd hi

@JohnRennie I am getting the message "Your Windows license will expire soon" again and again .. how to get rid of it?

@Abcd it means the copy of Windows on your laptop isn't activated.

@JohnRennie So... how to fix it?

4:37 PM

So the message is going to keep coming up unless you activate your copy of windows. Did you install windows yourself?

You need to go into the settings. I'm trying to remember where in the settings the activation setting is ...

Maybe the first question needs to be whether this copy of Windows was acquired through legal channels :P

@ACuriousMind Yeah, I figured that would be the better starting place

@Abcd aha, go into the settings then Update and Security, then click the Activation link on the left. I can provide screenshots if you struggle to find this.

Ok 1 minute

4:40 PM

FYI Windows 10 really doesn't seem to care if it's activated or not. I've had a "Activate Windows" watermark on my home PC for about a year now and nothing else has happened. I don't even notice the watermark unless I look for it

@JMac these things quickly drive us OCD types insane.

@JohnRennie Can you do it using Team viewer?

@Abcd yes, how are you going to get the password to me. Posting it here seems a little over generous :-)

Facebook?

@JohnRennie I dont think anyone here cares...I will post then you see and I'll delete

OK :-)

4:43 PM

@JohnRennie Come to PSS its empty

5:21 PM

The UK has had its hottest July day on record, with temperatures reaching 38.1C (100.6F) in Cambridge

Though in Chester it maxed out at 31.6°.

Paris apparently got to 42.6°.

Germany 41.5°

So it's time to drink some cold beer then.

It’s 84 here

Y’all are pussies

5:37 PM

@RyanUnger Fahrenheit. :P

@JohnRennie Goodness me. And to think Europe is supposed to be cooler

Captain Bohemian

5:55 PM

@JohnRennie eating shaved ice is better.

the air temperature actually had dropped for continuous several days due to raining until the passing day, when there was no rain in the afternoon so that the air temperature rose again though it has not been as high as those days before the rain.

6:10 PM

@JohnRennie its >40 here (Germany), im dying

those damn solar cycles

@JohnRennie one of the few days I’m glad not to be in Cambridge ;)

@NovaliumCompany pretty sure it’s evaporated away during production right?

I remember reading something like that for bread

Maybe I’m thinking of a different substance

Novalium Company

6:29 PM

How is TiO2 safe, but dangerous as a nanoparticle? I mean, wtf. TiO2 is made of nanoparticles no matter what.

in TeX, LaTeX and Friends, 3 mins ago, by Joseph Wright

@EmilioPisanty En-dash is used where 'and' or 'or' would fit, '-' is strictly a hyphen for word breaking

Novalium Company

I mean, nanoparticles are confusing. What's the difference between 1000 atoms of TiO2 and billions of atoms of TiO2?

damn, I learned something today

@NovaliumCompany nanoparticles of gold can also be dangerous

Novalium Company

@EmilioPisanty yeah, but why isn't gold dangerous when is made of nanoparticles?

@NovaliumCompany gold can be dangerous when it is made of nanoparticles, as I just said

Novalium Company

6:38 PM

@EmilioPisanty Nanoparticles are just gold but chopped up into 100 nm pieces? What's the difference then?

think of it as dust that is too fine-grained for your body's regular dust-stopping mechanisms to work effectively

@NovaliumCompany Freely moving nanoparticles can be inhaled and mess up your body

e.g. your lungs

if it's a microparticle, it'll be caught by the cilia in your airways and expelled

Novalium Company

Oh, so I can't breathe 100 nm gold nanoparticles because they "glued" together to the larger gold ingot?

And if they are not, it's dangerous

if it's too small, it can get past that and all the way to your alveoli, where the particles could collect, clogging up the airway. Or they could get absorbed into the bloodstream if they're small enough -- then they're too big to deal with using the mechanisms for chemical contamination, and it's already defeated the physical barriers

@NovaliumCompany basically

(to my understanding, though. I am not an expert on this.)

In any case, I assume that you've already checked the relevant Wikipedia page

Nanoparticles are particles between 1 and 100 nanometres (nm) in size with a surrounding interfacial layer. The interfacial layer is an integral part of nanoscale matter, fundamentally affecting all of its properties. The interfacial layer typically consists of ions, inorganic and organic molecules. Organic molecules coating inorganic nanoparticles are known as stabilizers, capping and surface ligands, or passivating agents. In nanotechnology, a particle is defined as a small object that behaves as a whole unit with respect to its transport and properties. Particles are further classified according...

... right???

6:43 PM

The question was, why do we need to subtract the velocity of the barrel to find the (exact) velocity of the shell or bullet. I have given a clear and accurate answer, and if there were people not bright enough to understand it, that's not my fault. — Michael Walsby 12 mins ago

Novalium Company

@EmilioPisanty Of course. But all I understood is that it's 100 nm of something, and exhibits different properties (somehow)

Health and safety hazards of nanomaterials

The health and safety hazards of nanomaterials include the potential toxicity of various types of nanomaterials, as well as fire and dust explosion hazards. Because nanotechnology is a recent development, the health and safety effects of exposures to nanomaterials, and what levels of exposure may be acceptable, are subjects of ongoing research. Of the possible hazards, inhalation exposure appears to present the most concern, with animal studies showing pulmonary effects such as inflammation, fibrosis, and carcinogenicity for some nanomaterials. Skin contact and ingestion exposure, and du...

Man this mentality bugs me "too right to be wrong even though everyone responding is saying elsewise"

@NovaliumCompany as in: you specifically looked for the Health Hazards section of that page

... right?

Novalium Company

@EmilioPisanty I just read the first few sentences of the page :P

6:45 PM

@NovaliumCompany ... an oversight which I understand you're remedying as we speak?

Novalium Company

Simply, if something is too small, it can get past your body's defence systems and start causing serious damage. (For example, it can get through the skin and into the blood) Am I right?

@NovaliumCompany yes.

Novalium Company

Cool

and, moreover, if it is small enough, it can get through cell and organelle membranes

while still being too big to break down chemically

now go. and. read.

before you keep asking.

Novalium Company

Yeah, I get your point :P

Wikipedia just explains things so complicatedly :P

6:48 PM

Seriously, please take Emilio's advice. You're very quick to ask; but being able to find these things for yourself is more useful than figuring out the answers to the questions

Novalium Company

@JMac Alright.

Let's do something. If I ask a question I can google, tell me to google. With time, I'll develop the habit of not asking everything that comes up in my mind here.

Curiosity is great; but it's even better when you're able to satisfy it on your own. It's not only your fault, everyone here is very willing to point you to the info, which obviously reinforces the behaviour, at least subconsciously.

Just checked in a respiratory tract model, 40 % of inhaled particles with an AMAD of 100 nm directly go the alveolar-interstitial region. That is a quite large fraction.

So for example at work we can have radioactive aerosols containing Co-60. Inhalation of 100 nm particles would cause 2.0E-8 Sv/Bq. Actually, however, workplace particles are more like 5 µm, which would cause only 6.2E-9 Sv/Bq.

7:27 PM

@NovaliumCompany this is a chat room not a personal habit remedying service. Please just google before you ask.

Novalium Company

7:41 PM

@JakeRose Alright

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