Wikipedia:Reference desk/Archives/Science/2013 December 17

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December 17

How are walnuts and Brazil nuts shelled in bulk?

It being Christmas, I've bought nuts to eat (quite why we British eat nuts at Christmas but not at other times is another question). Among them are Walnuts and Brazil nuts. For years I've wondered how these are produced shelled; the Brazil nut article even has a picture of shelled Brazil nuts. You struggle with the nutcrackers and maybe get a whole half walnut and 3 bits of the other half, your Brazil nut, after much work, might be 85% whole with 15% shards, yet you can buy bags of shelled walnuts (and pecans; same question and another "shelled" picture). In my experience the only nuts that can be shelled easily, giving a whole nut, are hazelnuts and (if you have a decent nutcracker) almonds. So how are shelled nuts produced? My private theory about tame worms that eat nutshells but not nuts is probably not the answer. Tonywalton ^Talk 00:14, 17 December 2013 (UTC)

Once again, youtube is your friend. μηδείς (talk) 00:23, 17 December 2013 (UTC)

Mmm. "A great big machine does it" seems to be the major theme there, unless I've missed some details. "Walnuts in, shells out at one place and walnuts out elsewhere". I'd kind of worked that out, but what happens in the middle? Thanks anyway. Tonywalton ^Talk 00:32, 17 December 2013 (UTC)

Well, it turns out that inside those machines there are these rather clever tamed worms that eat the shells... Actually, they will almost certainly use rollers to do the cracking. I assumed that some of these videos would show detail, but I am too busy to watch them myself. μηδείς (talk) 00:40, 17 December 2013 (UTC)

Speaking of worms, what's worse than biting into an apple and finding a worm? (And if you don't know the answer, you may have been in your shell too long.) ←Baseball Bugs ^{What's up, Doc?} carrots→ 9:19 pm, Today (UTC−5)

Two worms of course! 8.17.117.40 (talk) 14:32, 17 December 2013 (UTC)

Surely finding the two worms is far better than finding only one of them? Anyway the answer is half a worm. ;-) Dmcq (talk) 14:49, 17 December 2013 (UTC)

Sounds to me, as if the OP is using the cheap working-class [hazel/walnut cracker pliers ] meant for hazel, walnut and other tradition round nuts. There is no way to apply controlled force. Brazil, amound, etc, nuts are not round. They also need, controlled axial force to crack the nut with out crushing the kernel. I have just gone through all my kitchen draws to find my own, that cracks brazil's etc, perfectly, to photograph and upload -but it gone. I don't know if it got mislaid during our last house-move or if one of the wife's relatives took a fancy to it (they tend to treat my home, garage and garden shed as their local hardware and ironmongers shop) ( instead of installing a new cocktail bar, I should have set up a point-of-sales-counter ... hiss). Harrods of London is bound to stock such an item. This is the industrial, bench mounted and hand operated type. [1] Wrestling with all ones might, armed only with a pair of pliers that crushes the kernel as soon the the shell gives, is using the wrong tool for the job.--Aspro (talk) 17:26, 17 December 2013 (UTC)

• Draws? That's the second time you've used that. Is it dialectal? I wasn't able to find a dictionary entry with that meaning. μηδείς (talk) 18:18, 17 December 2013 (UTC)

Common misspelling of the word "drawers", resulting from some people's pronunciation of that word with the "er" syllable softened to the point of oblivion. SteveBaker (talk) 14:03, 18 December 2013 (UTC)

This is getting silly. A drawer can be a sliding container, or someone that draws stuff out or drawers can refer to a women’s certain undergarment. I simply stated that I went through my draws that I normally draw stuff out off. Some of the containers don't 'draw' or slide out – it is stuffed into boxes (many boxes in my case). So: When I said I when through my kitchen draws... I meant what I said: I went through my kitchen draws. It may be a bit like Americans saying, they fill up at the 'gas' station, when the fuel they are buying is actually in the liquid phase. They presume everyone has the sense to fill in the missing 'oleine'. This grammatical, syntactical transgression which is going off on a tangent doesn't add any benefit to the OP's question.So don't be so pedantically irritating ;-) --Aspro (talk) 16:02, 18 December 2013 (UTC)

I asked out of curiosity. Your defensiveness is unwarranted. Is this typical where you live? μηδείς (talk) 17:27, 18 December 2013 (UTC)

You may have well asked out of curiosity. Ask it then, as a separate question on say Reference desk/Miscellaneous. To concatenate extra questions that the OP hasn't asked, just fills up the replies with waffle that the OP may have no interest in but is 'forced' to wade though to get the answer they are seeking. Euclid created a Pons asinorum to explain triangles – you're turning explanation inside out into the legal understanding - to suggest that I'm now the defendant and you are the prosecution. It is a game, that teenagers like to play with their teaches, that wastes both time and patients and in so doing holds up the rest of the class from learning. All I am politely asking is that you stop going off on tangents that leads one away from the OP's original query.--Aspro (talk) 17:15, 19 December 2013 (UTC)

I'll assume you are joking, because this is a request for clarification in context, one you could have answered with a short sentence, instead of two paragraphs, if your worry for the OP's time were sincere. And we do not have any references to ask for that will explain why you personally have used this term. μηδείς (talk) 17:33, 19 December 2013 (UTC)

I recall a 1970s edition of the The Generation Game (a BBC gameshow in which contestants were given a difficult skill to try), in which they had brought-in an elderly Frenchman who spoke no English but was a professional walnut sheller. He had an earthenware tile shaped to fit over his thigh as a sort of anvil. He attacked each walnut by tapping it with a little hammer, and picked off the fragments by hand. The contestants made a bit of a hash of it, invariably smashing the kernels as well as the shells. So that's how it was done before they had big machines. Alansplodge (talk) 11:07, 20 December 2013 (UTC)

Approximately how much would the increased muscle on each arm weigh if:

a person who weighed 215 lbs became able to do five regular pull-ups when formerly he could only do five "150 lbs" pull-ups on a balance assist machine? Is it about half a pound per arm or what? Assume he remains close to 215 lbs. Thanks174.52.9.38 (talk) 04:40, 17 December 2013 (UTC)

In other words, how many pounds of muscle and supporting blood vessels does it take to do a 65 lb pull-up? μηδείς (talk) 04:51, 17 December 2013 (UTC)

I don't think it's as simple as that. First, the increased muscle mass is likely offset by a decrease in fat. Second, existing muscle can also be made stronger without increasing it's mass much. You might wonder why this extra strong muscle isn't the default state. I believe "out of tone" muscles use less energy, and evolution seems to have programmed our bodies to behave as if starvation is always just around the corner. StuRat (talk) 09:10, 17 December 2013 (UTC)

Then you should calculate a range. The upper of jus adding muscle without fat loss, and the lower with concomitant fat loss. μηδείς (talk) 12:29, 17 December 2013 (UTC)

I know that the force that a muscle can produce is proportional to it's cross-sectional area. The mass of the muscle is proportional to it's volume. The length of the muscle is determined by the length of the bones - so it won't change significantly as a person trains to lift bigger weights. So I'd expect the weight of the muscle to increase as the square of the amount of force it can exert. You're asking for a roughly 30% increase in force - so I'd expect to need to add about 70% (1.3x1.3=1.69) to the mass of the muscles involved. However, we don't know the mass of the muscles to start with - we don't know how well "toned" they are to start with - and (as others have pointed out), when you work harder, you tend to lose fat - which may somewhat compensate for the muscle increase. If I had to put a number on the weight of a muscle...it's about the same density as water, and an untrained upper arm muscle looks to me to have about a 50 cm² cross-section and a length of around 20cm - so if we approximate it as a cylinder, we have about 1 liter of volume - which is 1kg or so. So the maximum weight gain is probably 700g for each arm...3lbs maybe. I'd say that a 3lb increase is the most you'll see - the least could easily be zero. SteveBaker (talk) 15:58, 17 December 2013 (UTC)

I realize that your 1.5 lbs per arm is meant as an upper limit, but couldn't the upper limit be refined downward? Because that's like a quart and a half of buff per arm which sounds like a real strong guy. Thanks again.174.52.9.38 (talk) 20:17, 17 December 2013 (UTC)

Oops, it would be a pint and a half, not a quart and a half--probably a reasonable upper limit.174.52.9.38 (talk) 20:20, 17 December 2013 (UTC)

SteveBaker, how do you arrive at M ~ F²? If A ~ F and M ~ A⋅L with L constant, shouldn't M ~ F? -- ToE 21:25, 17 December 2013 (UTC)

Steve appears to be away on Wikibreak (perhaps enjoyng the holidays with his family) so before this question archives I should add that if the force is proportional to the muscular cross-sectional area then, yes, the weight of the muscle will increase linearly with the amount of force it can exert. (Intuitively, consider two of the same muscles side by side. You and I can, together, lift something twice as heavy as either of us can alone.) Keeping the rest of Steve's assumptions, this would reduce the maximum weight gain from 700g to 300g (about 10 oz) per arm. (It is certain to be more complicated that than, but this is a start.) -- ToE 12:46, 21 December 2013 (UTC)

• I doubt this was intended as a trick question, but it would make a good one. The fact is that the arm mass need not increase at all. A pull-up depends partly on the biceps (which are in the arm), but much more (the exact proportions depend on the type of pull-up) on the latissimus dorsi muscles (known as "lats", which are in the back. Looie496 (talk) 17:30, 17 December 2013 (UTC)

I took the question as the OP asking, given I can now do these pull-ups, how much muscle weight can I claim to have added? That would apply even if it were to other parts of the body. μηδείς (talk) 18:14, 17 December 2013 (UTC)

I think it's a lot more complicated than strength. I do a lot of pull-ups. I can do loads of sets of 6-8 reps; I usually stop when I get to 80-100 through boredom. I'm 82kg. There are lots of body builders at the gym who are way stronger than me but struggle with pull-ups and chin-ups. These guys weigh around 100kgs. Personally, I find pull-ups a lot easier than chin-ups, but then I tend to only do pull-ups. For me, a lot of the pull-up comes from holding the torso firm. When I've used those balance assist machines, I tend to collapse more, I guess because I'm kneeling on the platform and I find it much more difficult to hold the "tonic". --TrogWoolley (talk) 23:30, 17 December 2013 (UTC)

Conservation of energy in protein decomposition

The formation of proteins from amino acid requires energy. Then, according to the theory of conservation of energy, the decomposition of proteins into amino acid should produce energy. If so then why decomposition of protein in stomach by enzyme doesn't liberate much amount of energy (heat)?

You are right. Since the protein breakdown (also called Proteolysis) is a catabolic process, it should release energy. In fact, the breakdown of proteins in our stomach release energy, but the amount of energy released is not enough to cause any discomfort (or pain) in the stomach. Proteins in the diet serve primarily to build and maintain cells, but their chemical breakdown also provides energy, yielding close to the same 4 calories per gram as do carbohydrates. Carbohydrates have an average value of 4.1 calories per gram, proteins have 5.7 calories per gram, and fats have an average of 9.3 calories per gram. Scientist456 (talk) 15:07, 17 December 2013 (UTC)

According to the peptide bond article, breaking the bond releases 2–4 kcal/mol of energy. The molar mass of amino acids varies, glycine is only 75 g/mol, tryptophan 204 g/mol. Based on those figures, I'm guessing the breakdown of 100 g of proteins into amino acids would release between 1 and 6 kcal (depending on the specific amino acids). This is an insignificant amount compared to the more than 2000 kcal per day that an average person consumes (and which is ultimately released as heat). (the kcal I use is the same unit as the calorie Scientist456 uses btw: the energy needed to raise the temperature of 1 kg of water by 1 degree °C) Ssscienccce (talk) 22:48, 17 December 2013 (UTC)

Oh! Thank you for correcting me. Scientist456 (talk) 01:28, 18 December 2013 (UTC)

Correcting you? I wasn't aware I did that? If you refer to the calorie vs kcal issue, your use of calorie was correct, there are two units called calorie, differing by a factor 1000. They differ in their abbreviation, for the large (or dietary) calorie it's "Cal", for the small it's "cal", so 1 Cal = 1 kcal.

If you refer to the energy from breaking down proteins, your figure of about 4 calorie per gram is correct afaik, that's the energy from breaking down the amino acids, my figure only concerned the breaking of the peptide bonds. I'm just not sure where the 5.7 comes from, a different source? Ssscienccce (talk) 12:31, 18 December 2013 (UTC)

THIS ARTICLE may be useful for OP. Scientist456 (talk) 16:40, 18 December 2013 (UTC)

One more source: This paper assumes free energy of opening of a single peptide bond in the denatured state (ΔGop,D) equal to −2.7 kcal/mole. It also mentions that ΔG_op,N values cover the range from 0.2 to 10.0 kcal/mole for twelve specific peptide bonds... Ssscienccce (talk) 05:29, 19 December 2013 (UTC)

Formation and decomposition of protein

The formation of proteins from amino acid require energy. Then does the decomposition of protein into amino acid by digestive enzymes(trypsin,pepsin etc.) in alimentary canal release energy? If so what is its amount?Singh.ssm (talk) 9:00 pm, Yesterday (UTC−5)

See the multiple responses from where you asked this same/similar question a few days ago (#Conservation of energy in protein decomposition). DMacks (talk) 9:04 pm, Yesterday (UTC−5)

Please do not ask duplicate questions. μηδείς (talk) 05:12, 19 December 2013 (UTC)

Ink and dye

What physical or chemical properties distinguish ink from dye? Is it correct to say that ink is inorganic, whereas dye is organic? Scientist456 (talk) 15:34, 17 December 2013 (UTC)

No, and the answer will probably be context-specific. I used to hang around with a yarn engineer, and they distinguished between ink and dye based solely on when it got applied to the textile. Nimur (talk) 15:44, 17 December 2013 (UTC)

Well, ink usually washes out pretty easily. A useful dye needs to have some level of permanence -- possibly after some sort of treatment (such as heat). Looie496 (talk) 17:20, 17 December 2013 (UTC)

That article makes a lot of sense, actually. An ink in that context is localized dyeing - in other words, what makes an ink an ink is that you write (or in this case print) with it. So an ink has a requirement not only to be in one place, but not to be in some other. Wnt (talk) 17:24, 17 December 2013 (UTC)

Well, one could say that dye is is nothing more than ink unless a Mordant is employed.--Aspro (talk) 17:31, 17 December 2013 (UTC)

Permanent blue ink doesn't wash out easily. According to the dictionary definition ink is a solution used to write or print something whereas a dye is used to change the colour of something completely e.g. hair dye or fabric dye. As Nimur said I think it's mostly to do with what it's used for. Richerman (talk) 17:49, 17 December 2013 (UTC)

The wikipedia article on permanent markers show that it contains the mordant as a pyrrolidone. It is not what its used 'for' or upon but the chemical properties that makes for the diffidence between and ink and a dye.--Aspro (talk) 20:24, 17 December 2013 (UTC)

The difference between dye and pigment is more clear-cut: a pigment is a solid, insoluble in the liquid "vehicle", a dye is either a liquid itself or is dissolved in a liquid. Inks can be dye based or pigment based, but that would once again depend on the context. Ssscienccce (talk) 23:17, 17 December 2013 (UTC)

Yeah I don't know if permanence is that relevant as plenty of inks are fairly permanent. And inks can be dye based or pigment based, in fact some inkjet printers are known for using both with dye based ones often held to give better mixing and so used for CMYK and pigment ones to be more permanent and giving a sharper look so used for a special K intended primarily for text and stuff. I don't think there's generally much dispute that the stuff used in inkjet printers are inks.

As has been said, it's fairly context specific but I think whether something is called an ink or a dye depends at least somewhat on whether it's intended to diffuse or spread as part of the process of printing or application.

If we consider inkjet printers, where the coloured stuff is called ink (although as said it could be a dye or a pigment ink as well) or the many other uses such as pens etc the inks spreading may be a feature but generally not really intended (except that to ensure the ink application stays and is visible).

On the flip side we have Dye-sublimation printers which our article says should probably be called dye diffusion printers but doesn't dispute the dye bit (although does call the dyes, inks). In that case the dye diffusing in to the paper is part of the process of printing. (Although I imagine there be some artists applications where diffusion of inks is an important part of the process.) Noting of course that in a dye diffusion printer, you only want the dye to diffuse from your ribbon in to the paper and the areas where you want it to be applied, you don't want much further diffusion thoroughout the paper (you may want a small amount to give a more natural look, but then again, I wonder if inkjet printers also rely on this to some extent for photos although to a much finer level).

Of course we also can't ignore the history and marketing that like gives arise to such terms, for example Solid ink which uses a solid waxy coloured substances which needs to be melted before application has something that they call ink. Laser printing uses a powder which is baked on and although our article calls it ink a few times, it's generally called toner.

Nil Einne (talk) 06:47, 18 December 2013 (UTC)

• Once again, etymology saves the day. Ink comes from the Greek enkauston,[2]‎ meaning burnt in, and used in relation to signatures. Dye comes from an Old English word, deah, for hue or coloring.[3] Etymology Online is your friend. μηδείς (talk) 23:21, 18 December 2013 (UTC)

So that answers the question "What is the etymological difference between ink and dye?" But how does that resolve the OP's question about chemical and physical properties of ink and dye. Methinks the day is not yet saved. Richard Avery (talk) 07:46, 19 December 2013 (UTC)

You have to define your terms before you answer a question, much of the above is over terms. If you define ink as a pigment used for writing (essentially one-dimensional), as opposed to coloring cloth and other two-and three dimensional substances, then you get the necessity of fast-drying permanency in ink, and good diffusion and non-toxicity in dyes, and so forth. I assumed all that followed obviously, hence my leaving it unspoken. μηδείς (talk) 17:29, 19 December 2013 (UTC)

I don't know if you quite understood the above discussion in its entirety. I also don't know if your definitions have really solved anything as you implied, if anything they seem to conflict with some usages of the terms involved (which is actually in line with the above discussion). Nil Einne (talk) 16:16, 21 December 2013 (UTC)