Recent comments in /f/askscience

oheffendi t1_ja7cw7c wrote

Reply to comment by ECatPlay in If the fuel that goes in car engines is extracted from hydrocarbons, which consist of only Hydrogen and Carbon, and those hydrocarbons react with Oxygen in the air (combustion reaction), to produce CO2 and H2O, why do we get a bad smell from car exhaust fumes if both gases are odorless? by Protoflare

Many diesel cars, who traditionally have been the stinkiest of the bunch now use a special additive known by the trade name AdBlue (urea solution ) to help reduce NOx emissions. My car uses it and the reduction of the smell is quite noticeable.

3

_PM_ME_PANGOLINS_ t1_ja79622 wrote

Reply to comment by [deleted] in How is radioactive dating used to determine historical greenhouse gas levels and temperatures? by pog_irl

This is not true. Radiocarbon dating works on anything that exchanges carbon with the atmosphere, which includes air bubbles trapped in ice cores. You can approximate the year when the exchange stopped.

Other kinds of radioactive dating work on different materials, often rock.

3

Pun-pucking-tastic t1_ja75b05 wrote

Reply to comment by Suicicoo in If the fuel that goes in car engines is extracted from hydrocarbons, which consist of only Hydrogen and Carbon, and those hydrocarbons react with Oxygen in the air (combustion reaction), to produce CO2 and H2O, why do we get a bad smell from car exhaust fumes if both gases are odorless? by Protoflare

E-fuels are still carbohydrates. You get the same issues of aromatic compounds that are left unburnt, or incomplete combustion leading to CO emissions.

If you would run the engine with a supply of pure oxygen instead of air you could avoid the NOx problems but that would be ridiculously expensive to do.

Really, the only issue e-fuels don't have is the sulphur content, but that is already pretty low in modern car fuels.

7

mouldybun t1_ja72awh wrote

Reply to comment by andrewmmm in Is there any possible relation between the recent earthquakes in Turkey/Syria, Japan and Papua New Guinea? by Corvid-21

I noticed ephemeral in a book I read last year, funny you should choose that word... because I do feel I see it around more, but it must be purely the way I'm reacting to it, because in the book it's used to refer to non immortal, non digitized humans (the book is we are legion we are bob.) and it's sort of elevated the word to a new status... but I've been using google Vm's for years prior... and when you dont have a static IP its "ephemeral". Its odd how it's been this background thing and I literally never paid it any mind

Also, I think I did look up the definition... or the definition was explained in the book.

1

Suicicoo t1_ja7056u wrote

Reply to comment by ECatPlay in If the fuel that goes in car engines is extracted from hydrocarbons, which consist of only Hydrogen and Carbon, and those hydrocarbons react with Oxygen in the air (combustion reaction), to produce CO2 and H2O, why do we get a bad smell from car exhaust fumes if both gases are odorless? by Protoflare

would that be better with "clean" manufactured fuel (called E-Fuel in Germany) and a separate O2-supply?

4