Wikipedia:Reference desk/Archives/Science/2010 July 24
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July 24
[edit]What creature is this?
[edit]I found this this morning. What it exactly is ? Is it poisonous ? Jon Ascton (talk) 03:12, 24 July 2010 (UTC)
- I would assume a millipede, but it's hard to tell what species it is, as it's so blurry. However, it is not poisonous unless you eat it (even then it may not be). Where do you live? Perhaps that would help identify it. --The High Fin Sperm Whale 03:41, 24 July 2010 (UTC)
- I am in Punjab (North-Western India) —Preceding unsigned comment added by Jon Ascton (talk • contribs) 24 July 2010 (UTC)
- I do not see any legs, but the photo angle might cause this. To me it looks like a mealworm larva. Googlemeister (talk) 15:00, 26 July 2010 (UTC)
- Sorry, the legs ain't visible in pic, but it had legs, lots of it...
HD sunglasses and paint
[edit]I have now seen commercials for both paint and sunglasses claiming their products to somehow be related to high definition. It seems completely bogus to me (HD is about resolution on a monitor, not how bright colors are to the eye), but am I missing something? ?EVAUNIT神になった人間 06:49, 24 July 2010 (UTC)
Well for paint I would assume that the HD means "heavy duty" rather than High Definition. Sunglasses wise i think they're definitely using HD as 'short hand' for high quality because consumers associated HD as being high-quality so they want you to associate your sunglasses with that. Can't see there being a genuine application of HD in sun-glasses but you never know! (Oh and the paint company may be doing the same as the sunglasses one just instant assumption was 'heavy duty' when you say HD and paint). ny156uk (talk) 10:12, 24 July 2010 (UTC)
- No, it's not "heavy duty". I've also seen paint marketed as "high definition", which in that case really just meant they were trying to sell bright, bold and "vibrant" colors. Obviously it has nothing to do with HD displays, and would seem they are just trying to ride the coattails of the larger awareness about HD. I don't know about the sunglasses, but I would suspect that is also a marketing ploy. Dragons flight (talk) 16:57, 24 July 2010 (UTC)
- It's meaningless advertizing burble. I've seen mineral water be advertized a "fat-free" along similar lines! Physchim62 (talk) 19:26, 24 July 2010 (UTC)
- Well, at least that statement is objectively true — there really isn't any fat in mineral water. I agree that it's meaningless in the sense that it fails to distinguish the product from any other brand of mineral water (or any water...), but I'd say it's a grade of meaningless one above the "high definition" paint. In a similar vein, I saw a box of microwave popcorn proudly announcing that it is "100% whole grain". Well, yes — it won't pop otherwise.... TenOfAllTrades(talk) 19:41, 24 July 2010 (UTC)
- Fat free just makes people want to buy it. Just a gimmick. --Chemicalinterest (talk) 23:17, 24 July 2010 (UTC)
- Well arguably most paint is fairly high definition since you can't see any pixellation or lines except perhaps when you look at it very closely. Of course if you use multiple paints the result may not be very high definition Nil Einne (talk) 21:13, 25 July 2010 (UTC)
- Well, at least that statement is objectively true — there really isn't any fat in mineral water. I agree that it's meaningless in the sense that it fails to distinguish the product from any other brand of mineral water (or any water...), but I'd say it's a grade of meaningless one above the "high definition" paint. In a similar vein, I saw a box of microwave popcorn proudly announcing that it is "100% whole grain". Well, yes — it won't pop otherwise.... TenOfAllTrades(talk) 19:41, 24 July 2010 (UTC)
- It's meaningless advertizing burble. I've seen mineral water be advertized a "fat-free" along similar lines! Physchim62 (talk) 19:26, 24 July 2010 (UTC)
If you know English and only English...
[edit]...what are you missing in the field of science/technical developments? Is something out there of importance that is not being published in English?--Quest09 (talk) 13:29, 24 July 2010 (UTC)
- Slovenian poetry criticism and so on... 84.153.194.192 (talk) 14:11, 24 July 2010 (UTC)
- Did you mean science/technical Slovenian poetry? Cuddlyable3 (talk) 15:42, 24 July 2010 (UTC)
- Well, it seems so that all scientific innovations are monopoly of English using world, but it is not so. For example Japanese are actually ahead in many a field. Likewise the Germans were far ahead of us durning WW2 etc. Jon Ascton (talk) 14:27, 24 July 2010 (UTC)
- Yes the English speaking world (especially the US) is falling behind in most scientific achievements and manufacturing; just see where most things are made. The US is on a declining slide. --Chemicalinterest (talk) 14:54, 24 July 2010 (UTC)
- Chemicalinterest, I'm sorry for failing to understand whether your above comment is a joke or not. --Theurgist (talk) 15:20, 24 July 2010 (UTC)
- I am sure Chemicalinterest is not joking and that the proportion of new US patents granted to various countries is evidence for what he/she says. Cuddlyable3 (talk) 15:40, 24 July 2010 (UTC)
- It is not a joke. I really mean that. Compare US vs. China 100 years ago to US vs. China today. --Chemicalinterest (talk) 15:46, 24 July 2010 (UTC)
- That compares the two countries, but does it say anything for the information available in the language? Do the Chinese (for example) have a load of knowledge which has never been translated into English? Vimescarrot (talk) 16:29, 24 July 2010 (UTC)
- It is not a joke. I really mean that. Compare US vs. China 100 years ago to US vs. China today. --Chemicalinterest (talk) 15:46, 24 July 2010 (UTC)
- And citation needed anyway. Chemicalinterest, you've managed to give a number of GIGANTIC generalizations lately on here — could you please either spend some time elaborating on your own sources for this information, or provide some? Because otherwise this whole thing degenerates into Yahoo! Answers very quickly, and it is not helpful. --Mr.98 (talk) 16:30, 24 July 2010 (UTC)
- As Vimescarrot has hinted at, a large amount of scientific research is published in English, no matter the native language of the researchers. And colloboration largely happens in English. There are frequently postdoc programmes in countries like Japan which require no Japanese (although some basic level may be recommended/required so the people can live in Japan, e.g. [1]). This isn't to say there are no non English scientific journals, e.g. as discussed in Academic publishing in China there are. However many countries even those where English is not the native language may also have local English journals. And generally speaking if a researcher feels their research is particularly significant, they're going to try to publish it in a reputable international English journal as in the China case. In other words, while there is a fair amount of stuff out there that isn't in English, it won't generally be major breakthroughs that are missed.
- Note that an even without a language barrier, the poor regard of some of the journals, lack of indexing, lack of interest etc means that a fair amount of stuff may not be considered or well known among researchers in other countries. An example, I was looking in to cloud seeding a while back when it came up in an RD discussion. This is something widely praticed in China and from my searches, I found there was a fair amount of published research in English and more in Chinese however the state of play in Chinese research wasn't generally reflected or well discussed in more Westernised things I read. Another example, in Malaysia where English is largely the scientific language, various issues means from my experience many academics have rather poor publishing records particularly when it comes to internationally recognised scientific journals. They do publish somewhat in local journals which are usually in English but (well this was ~2-5 years ago) they were barely known or unknown, often not indexed nor easily available (well I'm sure you could get them via interloan) and I do wonder about the quality of the peer review (some of them may not even have been peer reviewed). Of course a lot of this is fairly applied research, relating to tropical plants and the like which isn't generally of that much interest to people in temperate countries. (Bearing in mind I have somewhat of a biological background so my greatest experience is there.)
- Nil Einne (talk) 18:02, 24 July 2010 (UTC)
- In the 15th and 16th century did scholars who read Latin but not English, German or French miss out on all the scientific and mathematical development, since folks in Germany, France and Britain were making breakthroughs in math, chemistry and physics? Not all that much, because Latin was a common language of publication then, just as English is now. English might even be a common language of publication researchers in different regions of China might or different regions of India, whose local dialect is not that intelligible nationally. Edison (talk) 19:58, 24 July 2010 (UTC)
- I know my answer above does not have anything to do with the question. The trend has been that way. China used to be a poverty-stricken, backward country... now it rivals the US. --Chemicalinterest (talk) 23:16, 24 July 2010 (UTC)
As a rule, if people make a discovery that they think the world should know about, they will make every effort to publish it in English. There is also significant science published in French, Russian, Japanese, and Chinese. Many of these journals, though, are abstracted in English or even fully translated. A person competent only in English will have no difficulty following developments in virtually any modern science. Looie496 (talk) 23:44, 24 July 2010 (UTC)
- There was a time a few decades ago where, if you were a chemistry major in the U.S., you were usually required to learn German. That's because most of the major players in the chemisty industry that weren't in the U.S., like DuPont and Dow and Gen Chem, were in Germany, like BASF and Bayer and IG Farben and the like. That's because, in the early 1900's, Germany had a near monopoly on the coal-tar dye industry, and that was at the time a major source of research in pure chemistry. Over time, petrochemicals became more important, but historically the two most important languages for a chemist to know were English and German. Even in the mid 1990's, when I was in school, it was still highly recommended to learn German as your required second language. (I chose French as my langauge, as I already had 7 years of it under my belt at that point). The rationale was that, although most modern literature was availible in English, much of the historical literature was in German, and if you wanted to get to the original paper on something, you had to read it in the original German. Today, however, almost everything is in English. It has become the lingua franca of most scientific literature. Even foreign journals often (but not always) publish an English version, and lots of research from non-English speaking countries is published in major English-language journals. --Jayron32 04:15, 25 July 2010 (UTC)
- Yes. As an undergraduate Science student in Australia 40 years ago, I was required to demonstrate my skills in a "Science Language". One had a choice of French, German or Russian. Given my current (lack of) ability in any of those languages, I am thrilled that almost everything is very quickly published in English these days. I've seen a couple of writers recently refer to Globish, reflecting the takeover of English in the science/tech world. HiLo48 (talk) 04:20, 25 July 2010 (UTC)
- It is probably accurate to say that English is sufficient. Any new development that were published in Chinese, for example, would quickly be translated to English. It's also reasonable to say that a foreign language skill is more relevant in business than academia. Most non-English-speaking academics will be more likely to translate their research papers into English. However, outside of "research", I often find schematics, datasheets, parts catalogs, and so on, written only in Chinese or Japanese. Not being able to read those documents does inhibit some knowledge transfer; but mostly about specific implementations, and not about general ideas. This is sort of the distinction between "research" and "development" - it is highly unlikely that a Chinese researcher would invent a new type of device and not tell the English-speaking world about it. But, it is very common for a specific implementation to remain untranslated. Nimur (talk) 00:02, 26 July 2010 (UTC)
poison ivy
[edit]if somebody got poison ivy in their eyes, would they get blind?--Horseluv10 15:16, 24 July 2010 (UTC) —Preceding unsigned comment added by Horseluv10 (talk • contribs)
- My understanding is that corneal damage is possible and that a doctor should be consulted in that situation. Looie496 (talk) 23:46, 24 July 2010 (UTC)
- We have several articles on the general topic of Toxicodendron species and their effects, the big three being poison ivy, poison oak (mainly Toxicodendron diversilobum), and the particularly brutal but luckily less common poison sumac. We also have a general article on urushiol-induced contact dermatitis, which is where the information on the medical effects should probably be centralized. Unfortunately it appears that the information on contact with the eye is somewhat limited; maybe that should be fixed. --Trovatore (talk) 00:00, 25 July 2010 (UTC)
- If someone got poison ivy or any other toxin in their eyes, their best bet would be to get to an emergency room ASAP, rather than poking around on the internet. ←Baseball Bugs What's up, Doc? carrots→ 05:22, 25 July 2010 (UTC)
- Or maybe it's just a curious kid wondering how careful you need to be around poison ivy. I'd say the question is ill defined. Do you mean around the eyelids? in which case there would very likely be temporary blindness due to the swelling of the lids. Or do you mean damage to the cornea? - in which case temporary blindness would occur and the possibility permanent blindness would be significant but not certain. Richard Avery (talk) 07:35, 25 July 2010 (UTC)
- I realize this is personal research, but I've had poison ivy all over my face, and in my eyes. They were swollen shut but I could still see if I pried open my eyelids. No permanent damage, although I was treated by a doctor to reduce the swelling. -- JSBillings 13:27, 25 July 2010 (UTC)
- Here is an 1893 medical journal which lists two men made blind by poison ivy: [2]. Given the prescientific methods used by medical doctors in those days, the blindness might have been a consequence of ill-advised treatments, or it could be due to infection caused by scratching.Edison (talk) 17:16, 25 July 2010 (UTC)
- It must be pretty common to get urushiol (the active agent) in the eyes, at least in small quantities, because if you get any on your fingers, it will take hours for even the smallest effects to show up, and you'll get it on everything you touch. Looie496 (talk) 17:57, 25 July 2010 (UTC)
- oh thanks for the information. i was just curious, and i was asking about getting it actually in your eye. Horseluv10 10:55, 26 July 2010 (UTC) —Preceding unsigned comment added by Horseluv10 (talk • contribs)
Multimeter
[edit]I have a multimeter as shown. Can I use it to measure AC mains ? In India it's about 220 v, I think. Is't safe ? Jon Ascton (talk) 15:52, 24 July 2010 (UTC)
- This is the sort of thing if you have to ask then the answer is likely no. Working with mains voltage can be very dangerous and you should not try it unless you know what you're doing. If you really are determined, make sure you connect everything before you turn on the mains switch. Do not touch the meter or cords while the switch is on. If you are trying to measure because you think something is broken then again you probably shouldn't do it at all. Nil Einne (talk) 16:20, 24 July 2010 (UTC)
- There will generally be a sticker somewhere on the meter (on that photo it's clearly visible around the sockets) that describes what safe range of voltages, currents etc you can work with. I would suspect 220v mains may be outside the recommended range of most normal multimeters. ~ mazca talk 16:48, 24 July 2010 (UTC)
- Actually, even $20 multimeters are usually rated for voltages above 220 AC. I'm not sure I have ever seen a multimeter that could not measure wall voltages. That said, I agree with Nil. If you aren't sure what you are doing, then you probably shouldn't be doing it. Dragons flight (talk) 17:07, 24 July 2010 (UTC)
- Or US$3 ones [3]. Okay that's actually measuring 110V but it looks like this [4] which is $9.99 not $5 but does have a 750V setting. I actually don't think I've seen one that doesn't have a similar setting although I've only seen a few (largely cheap) ones Nil Einne (talk) 18:05, 24 July 2010 (UTC)
- Actually, even $20 multimeters are usually rated for voltages above 220 AC. I'm not sure I have ever seen a multimeter that could not measure wall voltages. That said, I agree with Nil. If you aren't sure what you are doing, then you probably shouldn't be doing it. Dragons flight (talk) 17:07, 24 July 2010 (UTC)
- There will generally be a sticker somewhere on the meter (on that photo it's clearly visible around the sockets) that describes what safe range of voltages, currents etc you can work with. I would suspect 220v mains may be outside the recommended range of most normal multimeters. ~ mazca talk 16:48, 24 July 2010 (UTC)
- Clockwise of the off position on the dial is the setting for 750V ac - this is the one you would use - if you knew what you were doing.. As you have to ask about this I'd suggest getting some more experience on using multimeters (is there someone you can ask who can show you?) before plugging yourself into the mains. 83.100.252.126 (talk) 17:22, 24 July 2010 (UTC)
- I would never connect a cheap meter to a mains circuit at voltages of 480 volts or higher, unless the probes had fuses capable of interrupting a fault at the voltage level in question and at the maximum available fault current. The clearances and insulation levels are likely to be inadequate. Even so, the operator might need protective high voltage gloves, eye protection, and perhaps special protective garments. High voltages can sustain an arc which can incinerate everything for several feet around. A cheap meter could have leads which short, or could have an internal short. I am personally not as scared of 220, but I would treat it with respect. The suggestions of connecting the meter with the circuit dead are good if you are not experienced. Just because a voltage rating is on a meter does not automatically make it a safe operation to test at that voltage. Edison (talk) 19:48, 24 July 2010 (UTC)
Yes. Set the switch to just right of the OFF position to the setting for 750 VAC. Do not use any other setting and take good care not to come in contact yourself with the mains that you are probing. The warnings above are well intentioned but overblown. The probes, cables and meter are adequately insulated for 220V measurements and the notion of having fuses in the probes and special garments for a domestic mains voltage measurement is frankly ridiculous. Cuddlyable3 (talk) 23:09, 24 July 2010 (UTC)
- Cuddlyable3, Per your comment that special precautions for testing voltages at 480 and above are "frankly ridiculous:" We were talking past each other a bit, regarding 220 versus the higher voltage shown on the meter. I addressed the consequences of a short in the meter or faulty insulation on a test lead, when there might be over ten thousand amps of available fault current from the utility. If testing a vacuum tube radio, or a fused circuit in a house, there is an upstream fuse or breaker which would limit the fault current. If testing on the high side of the main breaker panel in a house, or a utility transformer secondary, such upstream protection may not be there. A premises might well have over 10,000 amps of available fault current on the high side of the main breaker or fuse panel, and a large flash could occur even at 220 or 240, though not likely a prolonged arc lasting minutes. A short at the meter even at 220 can cause a very large explosion, with injuries from heat and blast, worse than a short at an outlet or a toaster. If 480 volt leads from a large power transformer were inadvertently shorted, as by test leads or a multimeter, persistent and deadly high temperature arcing at can result. Note that I wrote about 480 volts and higher (the cheap meter illustrated has a 750 volt range), which can sustain an arc capable of incinerating the switchgear and everything in the vault. A meter, especially a cheap offbrand one, can have an internal short, a test lead can develop frayed insulation, and a plug can pop out of a meter and short to ground. A cheap meter is not necessarily safe to use at the highest voltage level selectable. Even a quality digital meter, with a high voltage probe, might not be safe to test utility primaries, even if the probe is rated to step down 30 kv to 300 va low meter input. A utility tester would use a meter the probe on a long stick which places him several feet away if there is a flash, and might be required to wear a facemask and protective clothing. Even at 240, a utility would require personnel to wear flame resistant clothing and protective glasses when testing voltage. It is all too easty to inadvertently short a test lead to ground, or for a wire to get pinched by a cover. I personally would not hesitate to test domestic 220 or 240 volt outlets with the meter shown. But a careless or inexperienced person could get into serious trouble touching test leads to such a meter to a high fault current source at the highest voltage level shown on the dial. Another problem area is that if a meter shows no voltage the circuit is not necessarily dead, since a test lead may have developed an open circuit or the meter might have a blown fuse or other problem. Ideally one would test on a live source, then test the "dead" circuit, then retest the live circuit. Edison (talk) 04:27, 25 July 2010 (UTC)
- My multimeter works fine measuring 120V power in the US. --Chemicalinterest (talk) 23:14, 24 July 2010 (UTC)
- I think Edison is right here. The probes should have fuses capable of interrupting the maximum available fault current at the voltage level in question. —Preceding unsigned comment added by 88.104.95.35 (talk) 23:23, 24 July 2010 (UTC)
- All the words of caution given here are most appropriate. My first Multimeter was an analogue machine - moving coil galvanometer etc. I was excitedly measuring everything I could find, including the resistances of all my electrical appliances and the mains output (240 V). After measuring a resistance I moved on to check the output from one general purpose outlet but I forgot to reset the Multimeter from "Resistance" to "AC voltage". Instantly one of the resistors in the Multimeter fused! I think it is still an open circuit to this day, so that is one "Resistance" setting that doesn't function. Don't bother measuring mains output until you have gained a lot of experience with your Multimeter and you are supremely confident you are following all the precautions you have been given here. Dolphin (t) 00:51, 25 July 2010 (UTC)
- Check whether the meter is certified as IEC 61010 CAT-III 600V (yes, six hundred) or better.[1][2][3] Don't use it on mains equipment unless it is. (Merely been rated at 220V or 600V, or even higher is not sufficient. It must be CAT-III.) Even if the meter is correctly rated, electricity can kill. If you had to ask the question at all you should call a licenced electriction. Mitch Ames (talk) 04:21, 25 July 2010 (UTC)
Playing Pokemon today and I wondered...
[edit]Is there any real animal that has an actual metal shell or exoskeleton? Or something close to that? I know that shells contain calcium but I was thinking more of something that eats minerals and then secretes pure metal on the outside. --95.148.106.219 (talk) 16:29, 24 July 2010 (UTC)
- Humans do excrete globs of liquid mercury if they get an overdose, but there is no animal I have ever heard of with a metal shell. --The High Fin Sperm Whale 17:30, 24 July 2010 (UTC)
- Many arthropods (and some worms, maybe Nereis - not sure) have increased metal (Mn, Zn, Fe) concentration in the parts of their exoskeleton that must be most wear-resistant. For insects that would be primarily the mandibles. Concentration of metals can reach over 10% by mass (!) according to the literature. What is not known, though, is whether those metals are incorporated in the chitin & protein matrix as nanoparticles, as mineral inclusions, or as ions. It is only pure, elemental metal (particles or nanoparticles) that you are asking about, AFAIU. --Dr Dima (talk) 18:21, 24 July 2010 (UTC)
- yes Nereis has zinc , some have metal-protein bonds, other have mineralised inorganic deposits (same ref) , this is mineralisation, not unlike teeth or odontodes, not pure metal.83.100.252.126 (talk) 19:50, 24 July 2010 (UTC)
- Is it that difficult to detect? Just put the insect part under a high-res DIC microscope and use an appropriate wavelength corresponding to the plasmon resonance of the metal. As long as the particles are not much smaller than 50 nm in diameter, they should be easy to detect. John Riemann Soong (talk) 18:48, 24 July 2010 (UTC)
- Beats me, too. If you can do it conclusively and in reasonable time, it could be a good paper. Just make sure you (a) ask your boss first if he or she doesn't mind you spending time on this, and (b) search the literature thoroughly to see if no-one has tried this before. I am a neuroscientist, so my knowledge is not exactly on the cutting edge of the insect mandible research, no pun intended. --Dr Dima (talk) 19:03, 24 July 2010 (UTC)
- Am I the only person here thinking about mantises (manti?) with hardened bio-metallic blades now? That would be an extremely fearsome mini-beast. --Kurt Shaped Box (talk) 22:52, 24 July 2010 (UTC)
- Animals don't need to use metals. A well-linked protein can be as hard or durable as metal and yet be much lighter. Spider silk, anyone? John Riemann Soong (talk) 16:14, 25 July 2010 (UTC)
- They're not animals (rather, they're algae) but diatoms have a silica cell wall, which is quite unusual. Brammers (talk/c) 18:24, 24 July 2010 (UTC)
- Grasses (Poaceae) also have silica crystals incorporated in their leaf-blade structure. It is thought to offer some protection against grazing. Silica is silicon dioxide, not a metal, though. --Dr Dima (talk) 18:34, 24 July 2010 (UTC)
- And silicon itself looks sort of metallic, but is not a metal — unless you're an astronomer. --Trovatore (talk) 22:57, 24 July 2010 (UTC)
- Probably not, most metals are either too rare or too reactive to be found on a shell. --Chemicalinterest (talk) 11:14, 26 July 2010 (UTC)
- And silicon itself looks sort of metallic, but is not a metal — unless you're an astronomer. --Trovatore (talk) 22:57, 24 July 2010 (UTC)
- Grasses (Poaceae) also have silica crystals incorporated in their leaf-blade structure. It is thought to offer some protection against grazing. Silica is silicon dioxide, not a metal, though. --Dr Dima (talk) 18:34, 24 July 2010 (UTC)
- Hermit crabs have been known to take discarded human items for shells. Some of them have probably been metal. Googlemeister (talk) 14:51, 26 July 2010 (UTC)
can silver nitrate eat cloth?
[edit]Last year after a particularly long organic chemistry lab I spilled a test tube and wiped it up with a towel. 2 weeks later at checkout, the towel had gone black, brown and blue and crumbled to dust when you touched it. 1 day later after touching the towel, I suddenly noticed my fingernails and parts of my hand had been stained black.
Now in that lab I had worked with sulfuric acid and silver nitrate. Silver nitrate seems likely for staining my hands (the skin recovered within a week...the fingernails took several months to grow out) ... but would it eat cloth? It seems unlikely I would have worked with both in the same test tube (doesn't the combination make an especially strong oxidiser? how strong of a Lewis acid is Ag+ anyway)? John Riemann Soong (talk) 18:43, 24 July 2010 (UTC)
- Silver nitrate is both oxidising and corrosive [5], similarly mineral acids will destroy cellulose over time too.83.100.252.126 (talk) 20:07, 24 July 2010 (UTC)
- Well I got that silver nitrate is at least mildly corrosive and oxidising. But it will eat through cellulose? John Riemann Soong (talk) 16:13, 25 July 2010 (UTC)
- In the long term, especially in the presense of light it's equivalent to nitric acid/NO2 - I'd guess yes. 87.102.43.171 (talk) 13:50, 26 July 2010 (UTC)
- Well I got that silver nitrate is at least mildly corrosive and oxidising. But it will eat through cellulose? John Riemann Soong (talk) 16:13, 25 July 2010 (UTC)
white horse wind wave.
[edit]Description of a "white Horse" wind wave. The Wikipedia listings of the Beaufort wind scale use the term "white horse" to describe a white cap at low wind velocity. There is no clear definition or illustration. What exactly is a "white Horse" in this context? Science Searches lead nowhere or to the color of horses. —Preceding unsigned comment added by RManns (talk • contribs) 21:03, 24 July 2010 (UTC)
- A white horse is just the breaking cap of a wave. Once the wind reaches about 7 knots (Force 3), a few white horses become visible, by the time the wind speed has reached about 22 knots (Force 6), white horses are everywhere. The photos of sea states from the NOAA here are not great but they may help. Mikenorton (talk) 23:19, 24 July 2010 (UTC)
- Doesn't seem to be a scientific term, but Google Web and Google Books searches find usages. The term was defined as long ago as the Encyclopedia Americana of 1829. Looie496 (talk) 23:25, 24 July 2010 (UTC)
Pocket Monsters Special Yellow (final battle): Lava surfing?
[edit]Is it possible to surf on lava, or is it too viscous? --138.110.206.99 (talk) 21:52, 24 July 2010 (UTC)
- Melt your surfboard. --Chemicalinterest (talk) 23:09, 24 July 2010 (UTC)
- More like incinerate. Pāhoehoe lava might be liquid enough to surf on, but a bit on the warmish side. Looie496 (talk) 00:31, 25 July 2010 (UTC)
- Assuming you could make a surfboard that could withstand the heat, and you could withstand the heat, then yes, you could. Because even the lowest-viscosity lava (flood basalt) is more viscus than water, than it might be easier to surf on it. Now, some lava is too viscous, like rhyolite lava (about consistency of toothpaste), so surfing may not work on that. On the plus side, it's cooler in temperature... QFL 24-7 bla bla bla ¤ cntrb ¤ kids ¤ pics 04:31, 25 July 2010 (UTC)
- More like incinerate. Pāhoehoe lava might be liquid enough to surf on, but a bit on the warmish side. Looie496 (talk) 00:31, 25 July 2010 (UTC)
- Just to be clear, are you asking whether it is possible to surf on lava in real life? Or, are you asking if it is possible to surf on lava in Pokemon Yellow? 86.164.66.83 (talk) 17:45, 25 July 2010 (UTC)
- It's probably the latter, making this a VERY funny thread! DRosenbach (Talk | Contribs) 18:30, 25 July 2010 (UTC)
- Well, both seem likely interpretations of what they wrote to me, although the former is more suited to this desk, and a more interesting question. For the latter, I'm pretty sure there's no surfing on lava, but I never had this edition myself. I don't see it mentioned in any walkthroughs. Of course, there weren't really any colours on the screen in those early versions, so it would be possible to interpret some body of water as lava. 86.164.66.83 (talk) 18:47, 25 July 2010 (UTC)
- It's probably the latter, making this a VERY funny thread! DRosenbach (Talk | Contribs) 18:30, 25 July 2010 (UTC)
I was referring to the final battle of the Yellow arc of Pocket Monsters Special, which takes place in the crater of a volcano; the protagonist surfs on lava to avoid Lance's attacks. --138.110.206.101 (talk) 21:14, 25 July 2010 (UTC)
Budgerigars and reflection recognition
[edit]Anyone that's ever owned a budgie will probably have seen this - they seem to have an ability to recognise even the smallest and most fractured reflection of itself as another bird with which to interact. For example, a budgie can see another budgie and recognize it as another budgie (speaking from personal experience) in items such as a tarnished, scratched-up Zippo lighter, the wooden top of a speaker cabinet, a metal clip used to hold cuttlefish bone (reflective bit can be no more than 2mm square), fingernails, the scratched-up screen of a mobile phone, a bit of clear plastic shrink wrap from a CD...
How does this work, exactly? As a human, I can *barely* make out a reflection of *something* in these things - yet the budgie will sing his little heart out and do his little display dances as though it's a brand new friend. --Kurt Shaped Box (talk) 23:01, 24 July 2010 (UTC)
- Are you sure they think it's another budgie? Maybe they just like shiny things. But birds have much better (day) vision than humans. Ariel. (talk) 03:19, 25 July 2010 (UTC)