Wikipedia:Reference desk/Archives/Science/2014 January 27

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January 27[edit]

Difference[edit]

Whats the diff tween nuclear scince and atomic scince..?--31.55.102.122 (talk) 01:17, 27 January 2014 (UTC)[reply]

With one, the future's so bright, you gotta wear shades (unless you're Feynman) Wnt (talk) 17:12, 27 January 2014 (UTC)[reply]
Technically, nuclear science deals with the nucleus of the atom, while atomic science, if there was such a term, would presumably deal with the entire atom. However, this is just chemistry. But, somebody might also use "atomic science" as a synonym for nuclear science, I suppose.StuRat (talk) 03:48, 27 January 2014 (UTC)[reply]
Yes, nuclear science has the connotation of dealing with radioactive reactions; fission or fusion. I am not sure atomic science is really used as a separate term, but there are such books as The Elements: Their Origin, Abundance, and Distribution: P. A. Cox that deal with the elements as such, whether inherently radioactive or not. μηδείς (talk) 04:03, 27 January 2014 (UTC)[reply]
  • See this graph and this graph to see the usage of the terms in English books that Google has scanned. "Atomic" as the term was more popular at first and then "Nuclear" became the new buzzword. Richard-of-Earth (talk) 10:46, 27 January 2014 (UTC)[reply]
Yes, that's right. They are synonyms, but atomic science is now dated. SpinningSpark 11:21, 27 January 2014 (UTC)[reply]
However, out article on Atomic physics does make a distinction from Nuclear physics and it is exactly as StuRat supposes above. Nuclear physics is addresses only the nucleus and atomic physics addresses the with the whole atom. But that seems to be a technical distinction and both articles lack citations on the difference. Richard-of-Earth (talk) 11:34, 27 January 2014 (UTC)[reply]

Kriegslok[edit]

Many railfans know how to distinguish different types of steam locomotives by sound; e.g. the "Shay" narrow-gauge engine puffs at six beats to the bar, the "Lord Nelson class" express engine at eight beats to the bar, many of the Gresley locomotives have a syncopated beat because of the derived valve gear, etc., etc. So can anyone describe to me how a German Kriegslok freight locomotive sounds, especially in comparison to a French freight engine? Thanks in advance! 67.169.83.209 (talk) 06:14, 27 January 2014 (UTC)[reply]

Youtube has many examples you can listen to such as [1]. SpinningSpark 11:19, 27 January 2014 (UTC)[reply]
Oh, and don't miss this wartime propaganda film about production of the locomotive. SpinningSpark 11:26, 27 January 2014 (UTC)[reply]
Thanks! It sounds to me like the sound of the exhaust is rather sharp -- which would make sense because to simplify production, the pistons probably weren't chamfered like they are in many other steam locomotives. 67.169.83.209 (talk) 05:31, 28 January 2014 (UTC)[reply]

download offline medical division content only[edit]

Dear Sir I am a pharmacist and I wish to download offline data of wikipedia of what is concerning the medical section. How can I download only that speciality. Do I have to download the 9 GB zm file or there is a file for each devision that can be downloaded. Thank you — Preceding unsigned comment added by 62.114.71.69 (talk) 13:17, 27 January 2014 (UTC)[reply]

Each Wikipedia article has a "download/print" section which you can use to download individual articles. ←Baseball Bugs What's up, Doc? carrots→ 13:43, 27 January 2014 (UTC)[reply]
Downloading one article at a time will take a very long time. A database download should be a lot simpler. Once you have the full database you can use queries and filters to select the files you want to keep. Roger (Dodger67) (talk) 15:45, 27 January 2014 (UTC)[reply]
You can also create a "book" with a selection of pages. There is a link in the left column of the page. You can add an entire category to it, then export in several formats including PDF. Katie R (talk) 17:38, 27 January 2014 (UTC)[reply]
See Book creator for details, see also: categories[not very helpful here] ~:71.20.250.51 (talk) 00:25, 28 January 2014 (UTC) [Modfied:00:29, 28 January 2014 (UTC)][reply]

Mixing powdered cinnamon into water[edit]

Today I was trying to stir ground cinnamon into my mass market triple shot iced coffee. I noticed the ground cinnamon just did not want to blend into the coffee. It wanted to float on top and resisted mixing. What's this property called? --Navstar (talk) 23:01, 27 January 2014 (UTC)[reply]

[Banned user]

Is there an element of hydrophobicity involved? Dbfirs 23:17, 27 January 2014 (UTC)[reply]

[Banned user]

I believe most chemically inert, water-insoluble powders can act similarly hydrophobic. See the pictures at Superhydrophobe, but think about the powder in the liquid instead of the liquid on a rough surface. Wetting is the converse process, and also has some good pictures. When you have granular material instead of surface roughness discussed in the articles, then clumps can form where the outside is wetted and cohesive, but the inside stays dry, and this makes it even more difficult to mix into an homogenous suspension. I can't find a WP article that specifically discusses the hydrophobic behavior of powders, but Mixing_(process_engineering) alludes to some of these issues. SemanticMantis (talk) 23:47, 27 January 2014 (UTC)[reply]
Now for some practical suggestions for your case:
1) Mixing works better at higher temperatures, so mix in the cinnamon to hot coffee, then add the ice. Of course, if it's already iced when you get it, this option is out.
2) Pour a small portion of the coffee into a large container with a top, add the cinnamon, seal the top, shake well, then open it up and add the rest.
3) Use a liquid cinnamon flavoring agent instead of powered cinnamon. Of course, this is likely to contain sugar and other items you may want to avoid. StuRat (talk) 00:44, 28 January 2014 (UTC)[reply]
(Practical solutions to avoid situation described)
4) Simply add the cinnamon with the ground coffee before you brew it. —(For iced coffee, brew double-strength before adding ice)
5) Use oil of cinnamon (one or two drops); but, should add cream/milk to act as an emulsifier. ~E:71.20.250.51 (talk) 01:15, 28 January 2014 (UTC)[reply]
Note that 5 is a variation on 3, only 3 already has the emulsifier mixed in. StuRat (talk) 02:20, 28 January 2014 (UTC)[reply]
My grandmother used to sometimes add a few drops of brandy to dried spices. Presumably, as alcohol is a wetting agent this helped but I can find no references. So maybe this is Folklore. Mind you, as your end point is a nice cup of iced coffee, then a dollop of brandy can only improve things.--Aspro (talk) 17:06, 28 January 2014 (UTC)[reply]
Yes, I think that would help form a tincture of the tasty chemicals. There's a few things going on here. In cinnamon, there are all kinds of volatile organic compounds that carry flavor, that are soluble in water/alcohol. But most of the cinnamon powder, by weight or volume, is insoluble cellulose. SemanticMantis (talk) 17:22, 28 January 2014 (UTC)[reply]
That's is a good point. As cinnamon is bark consisting of cellulose and lignite, then even finely ground it will just float. Infusing the coffee with a cinnamon stick (and then removing) might be what the OP is after. However, if it is filtered coffee, the filter will remove those grounds. Still, the OP mentions “mass market triple shot iced coffee”. Well, I don't know what mass market coffee is, unless he means something like nescafé in which case its is like trying to [make a silk purse of a sow's ear]. Tap-water is a better re-hydrant. So, in short he may just need to infuse a suitable sized bit of cinnamon stick for a few minutes in hot water and then add the coffee to that water infusion.--Aspro (talk) 20:07, 28 January 2014 (UTC)[reply]
Yep, most of the flavor of cinnamon comes from compounds that are only sparingly soluble in water, but are much more soluble in alcohol: mostly cinnamaldehyde and some ethyl cinnamate. The former is widely used as a flavoring agent. TenOfAllTrades(talk) 03:31, 29 January 2014 (UTC)[reply]