Wikipedia:Reference desk/Archives/Science/2014 April 26

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April 26

Question about a superconductivity

Is it, may be doing a very colder static of a metals for a superconductivity?--Alex Sazonov (talk) 09:21, 26 April 2014 (UTC)

Are all metals superconductors ?

...below a critical temperature ? How about nonmetals and other materials ? Our article says "certain materials", but perhaps some just aren't practical because the critical temp is a trillionth of a degree above absolute zero ? So, in theory, should everything become a superconductor if close enough to A.Z. ? If not, do we know why ? StuRat (talk) 12:41, 26 April 2014 (UTC)

I been thinking, that a some may been doing a static situation of all metals in which they always had been a superconductivity and temperature modes always are beenig not in it.--Alex Sazonov (talk) 15:08, 26 April 2014 (UTC)

It been seems me, that a some chemical covereds may been doing a static situation of all metals in which they always had been a superconductivity, is it been really?--Alex Sazonov (talk) 07:38, 27 April 2014 (UTC)

If been done a some chemical covered of a metal, is it this metal been done a overcome of internal heating of it which always been modify a internal static structure of this metal?--Alex Sazonov (talk) 12:32, 27 April 2014 (UTC)

As far as I can see, current theory of superconductivity says some metals (at least copper, silver and gold) do not superconduct. They have only one electron on their outermost shell, which prevents cooper pair formation. This is still somewhat an open question though; there are still open questions on how superconductivity works, and proving a negative can be hard. For deeper discussion on the subject search the net e.g. superconductor gold copper. 88.112.50.121 (talk) 14:37, 27 April 2014 (UTC)

Very much thanks for you, I always been seen this problem about a superconductivity of a metals as a general question in a science physics of a metalling, thats I always been thinking that always been none a science physics of a private case of a metalling, because as I see, that a science physics of a low temperature always is not been a general science physics. Be good, if I read about a superconductivity in English as a private case of a metalling. I’m lets a question after.--Alex Sazonov (talk) 15:45, 27 April 2014 (UTC)

Is it been, a statics temperature modes in a copper, a silver and a gold always are beening another than it always been in all other metals?--Alex Sazonov (talk) 18:14, 27 April 2014 (UTC)

It is been, in during by steps of coldering of all metals always are been modify a properties of it, because in that situation in all metals always been doing another a static electrical charge.--Alex Sazonov (talk) 19:06, 28 April 2014 (UTC)

You need an attractive interaction between the electrons for Cooper pairs to form. The exchange of virtual phonons (quantized lattice vibration) provides for such an attractive force, but in case of gold you don't get an atractive interaction. Count Iblis (talk) 20:57, 28 April 2014 (UTC)

It is been, a property of transferring a powerful electric volts always is beening a general property of all metals, that’s why I always thinking that a science general physics of a metalling is been always right that all metals had been a superconductivity.--Alex Sazonov (talk) 07:29, 29 April 2014 (UTC)

Is it been, a powerful electric volts are beenig a superconduction of all metals?--Alex Sazonov (talk) 09:07, 29 April 2014 (UTC)

Is a electronics of a powerful electric volts been?--Alex Sazonov (talk) 09:51, 29 April 2014 (UTC)

Hazmat cleanup

What's the standard procedure for cleaning up a major (1000 L or more) spill of concentrated sulfuric acid? Thanks in advance! 24.5.122.13 (talk) 18:17, 26 April 2014 (UTC)

Same as a spill in a lab. Use a dry agent such as sodium carbonate and or calcium hydroxide. Then shovel up into acid resistant containers. Flush site with loads of water. Google: HAL-02-07/1/14/HWCMP01-P.DOC/10/03/06 --Aspro (talk) 19:38, 26 April 2014 (UTC)

So, let me see if I got this right: Dump a truckload of slaked lime on the spill site, spread it out (most likely using earth-moving equipment), bulldoze into stainless steel- or Teflon-lined waste containers, and then hose down the area with a water tender -- is that correct? 24.5.122.13 (talk) 20:05, 26 April 2014 (UTC)

Wouldn't they also evacuate the area and wear chem suits with breathing equipment ? StuRat (talk) 20:11, 26 April 2014 (UTC)

Right, they would DEFINITELY need at least gas masks, to protect from the acid aerosol (especially if fire is also involved, as it is in my scenario). 24.5.122.13 (talk) 20:15, 26 April 2014 (UTC)

Doesn't my ref above: HAL-02-07/1/14/HWCMP01-P.DOC/10/03/06 mention all that? That is why I posted it.--Aspro (talk) 23:48, 26 April 2014 (UTC)

People are more likely to read links. Why didn't you post a link ? StuRat (talk) 16:48, 27 April 2014 (UTC)

Good question. Answer: Wikipedia bans all the links I found. As simple as that. If you know of a way around this, please do tell.--Aspro (talk) 17:31, 27 April 2014 (UTC)

In that case, you might want to list why Wikipedia says they banned it, and why you think it's OK. StuRat (talk) 16:20, 28 April 2014 (UTC)

Well, [1] explains this. Yet, the document I refer to is not meant to be excluded. So it is a no brainer. I.E, it is the pan google link that is blocked not the document.--Aspro (talk) 20:38, 28 April 2014 (UTC)

The United States Department of Transportation produces a free guide, the Emergency Response Guide, which they distribute to fire departments, public safety organizations, and private sector partners. (I keep a copy in my car, in case I ever need to know how many meters to stay away from a fire, because in the course of an ordinary week, I often drive near all kinds of dangerous-but-clearly-placarded stuff)! You can download a free PDF it online : Emergency Response Guide 2012.

For sulfuric acid, (when DOT-placarded as 1830), use guide #137 for water-reactive corrosive substances. (See! That's exactly why you want to keep this guide-book in your car: the acid reacts with water - so you shouldn't just start spraying water on a vehicle-fire, which can make a bad situation explosively worse! Your first instincts aren't always correct for hazardous substance incidents). Probably not a good idea to dump a truckload of slaked lime on it either. That isn't even the correct action for a small spill - don't you remember the chemistry-slogan: always add acid to water. The "always" means "always" - especially in an emergency! Never add water to acid! And if there's a spill, why would you add a reactive substance? It can explode.

You can read the guide book, and you should pay attention to all the caveats - there are loads of other variations of sulfuric acid containment best-practices. But among the other good advice: "As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions."

It is also worth noting that Guide #137 (for sulfuric acid) does not mention using lime. That is an emergency-procedure for other types of hazardous materials. For sulfuric acid spills, the area should be covered with dry earth or sand, and later removed using plastic containers. Yet another reason why you ought to use a reliable source, instead of relying on a random internet web-search! There are loads of websites with bad and dangerous advice on chemical procedures; but you should probably rely on a reputable source to inform the best course of action. Obviously, the specific circumstances of your spill might contravene published advice; there's no such thing as a "standard" catastrophe!

Nimur (talk) 20:18, 26 April 2014 (UTC)

So, truckload of dry sand, spread it out over the spill and bulldoze into acid-resistant containers, right? (I presume that any victims lying in the pool of acid -- and most likely screaming in agony with third-degree chemical burns -- will first have to be carried or winched to safety. Does the person doing this also have to wear acid-proof clothing?) 24.5.122.13 (talk) 20:57, 26 April 2014 (UTC)

And for the record, my scenario is a highly non-standard disaster. Remember I was asking just a short while ago about how big a piece of avalanche debris has to be to rupture a gas pipeline? Well, I decided to get really mean and make it a big rig carrying concentrated vitriol. So we have a gas explosion and fire, a massive acid leak right next to it, a downed high-voltage power line close by, plus a nearby river bursting its banks due to a debris dam (see below), plus all the other carnage typically found in a major avalanche scenario. And to top it all off, the avalanche has also cut the road, so all the equipment has to be airlifted in. 24.5.122.13 (talk) 21:06, 26 April 2014 (UTC)

If concentrated sulphuric acid got into the storm sewers, it would need to be diluted or neutralized there, and the metal components of the sewer might be corroded and in need of replacement. The site where the storm sewer drains would also be contaminated, perhaps killing fish in the lake. (Some storm sewers drain directly, while others go to sewage treatment plants first.) StuRat (talk) 20:28, 26 April 2014 (UTC)

It would I think, help to know if 24.5.122.13 is an author researching for a novel or some such. Otherwise, his many-fold questions seem lazy . [2] Again I suggest. Read HAL-02-07/1/14/HWCMP01-P.DOC/10/03/06--Aspro (talk) 00:06, 27 April 2014 (UTC)

Sure I am -- I thought you'd have figured it out by now. 24.5.122.13 (talk) 01:51, 27 April 2014 (UTC)

Just took a quick look at the first few pages of the document -- it appears that this is a plan for a hazardous waste site, so most likely any acid to be disposed of at the site would not be highly concentrated as it would be in my disaster scenario. Hence the use of neutralizing agents would be permissible in this application, but this would not automatically be applicable to a spill of highly concentrated 98% sulfuric acid, as in my scenario. 24.5.122.13 (talk) 02:01, 27 April 2014 (UTC)

Holy Moly, how can you aspire to be a writer without being a reader first. Lower down it covers 'SULFURIC ACID (>51%). That includes concentrated!!! Good job your plot doesn’t involve terrorists trying to separate plutonium from dicaesium plutonium hexachloride. Umm???? I have herd it said that everybody has a novel in them and you have just given me an idea for a plot which involves … No not going to tell you. You will have to buy a copy of my book to discover how Nicole Kidman playing the part of an unappreciated radiographer, saves Washington DC from being fried by a terrorist group that have got their hands on a thermonuclear weapon. With no more than just a bottle of Contrast medium that she had to steal from the hospital where she works , (whose legal gooks are hunting her down down for misappropriation of hospital supplies) Plot Spoiler: It ends happily with her grateful hero (or stupid idiot that allowed the terrorists to get their hands on a functional bomb in the first place), buying her a new fitted kitchen. Closing scene is were, as she is icing a cake, baked in her new kitchen, there is a power failure and she sees the little sliver balls on top glowing in the dark – maybe her hero was not so innocent and naive as she believed? - leaving the audience on tenterhooks for he next sequel.--Aspro (talk) 17:27, 27 April 2014 (UTC)

Holy Moly, how can you expect someone to read 300+ pages of highly specialized technical writing -- only a small portion of which is actually directly relevant to the matter at hand -- in a single sitting? I'll read it, of course, but that will take me at least a few days. As for your book: best of luck with that, maybe I'll beta-read it if you want? 24.5.122.13 (talk) 23:13, 27 April 2014 (UTC)

Although I don't think that it's possible to detect radioactive material of any kind using contrast medium -- your heroine will have to use something else, like a scintillator, to do her part. 24.5.122.13 (talk) 23:25, 27 April 2014 (UTC)

Where did I say that the contrast medium had any part in detecting radioactivity? It is a given that the dirty-bomb that her hero/stupid idiot boyfriend let the terrorists have, contains radioactive material – it is self explanatory by definition. Her brilliant ploy was to stop it going critical and ruining her mascara, by pouring in some boron and iodine contrast agents.Computed tomography imaging of transferrin targeting liposomes encapsulating both boron and iodine contrast agents by convection-enhanced delivery to F98 rat glioma for boron neutron capture therapy..--Aspro (talk) 13:14, 28 April 2014 (UTC)

Dirty bomb, or thermonuclear weapon? Because these are COMPLETELY different types of devices. And if the former, then it might not NEED to go critical, and in that case adding boron will NOT stop it from working. As for stopping a thermonuclear weapon, adding boron is not necessary to stop it from exploding -- in order to add the boron, your heroine will have to (partially) disassemble the primary assembly, which ALONE will prevent the device from achieving a nuclear yield -- the primary relies on explosive lenses exploding simultaneously to create the implosion which compresses the fissile material to achieve critical mass, and if even a few of these explosive lenses fail to go off, the fissile material will be dispersed rather than compressed. 24.5.122.13 (talk) 02:25, 29 April 2014 (UTC)

Got the feeling that your tail is trying to wag the dog. You could try writing children’s novels instead. There is no demarcation line between dirty and thermonuclear. The efficiency of yield to mass is what is important. A second-hand (one careful owner) device may be out of spec by the time the terrorists receive it. IE, the tritium balloon and implosion components may be in need of replacement – these buckets-of-instant-sunshine need rebuilding about every six years. As you may or may not know, the tritium balloon (in the core) has a pipe that extends out of the core assembly. Viewing other films there is a lot of cinematographic licence to be had here. If said device, is not got to in-time, Washington gets fried. If it is got to in time and only partly dismantled when time runs out, Nichols Kiddman gets more than singed eyebrows if it fizzles (one has to keep the cinema audience on tenter hooks). BUT she, in her wisdom, pours a boron rich mixture down the titanium port to the tritium balloon in the centre of the assembly. Utter tosh I know, but the last time Nichol Kiddman dealt with a nuclear device, the films script writers probably earned more (than I your leading me to believe) you ever will. You need to understand the research your doing other wise everybody would be churning out best seller. Incidentally, the neutron flux (in the film I'm referring to) would have given her a fatal dose from that distance. --Aspro (talk) 22:19, 30 April 2014 (UTC)

Back on topic: I've read the spill response plan for that gold mine in Australia, and the MSDS DOES in fact say to cover the acid with sodium bicarbonate or a mixture of sodium carbonate and calcium hydroxide -- but that doesn't stop the other emergency response guide from saying to cover it with dry sand and NOT to use neutralizing agents. So how can I (or anyone else, for that matter) tell which one is right and which one is wrong? 24.5.122.13 (talk) 02:30, 29 April 2014 (UTC)

Well, the answer depends. Who's doing the emergency response? What laws and regulations apply? Who has jurisdiction and gets to make the decisions? In North America, the Department of Transportation guidelines are more relevant, because that's what fire departments and emergency responders will probably follow. But any individual incident could be handled by a different department, or a different on-scene commander; expeditious response might require actions that don't play out "by the book;” and even if all the rules are followed, special regional laws and safety regulations might apply and a legal counsel or attorney might be needed to sort through the local and federal requirements... it's a mess, literally! If you want to be thorough and accurate, you can read up and perform case studies on a number of previous incidents to see what actually has happened. Nimur (talk) 05:29, 30 April 2014 (UTC)

Just discussed this with a hazmat expert earlier today -- she told me that the best way to deal with a sulfuric acid spill is to (1) contain the spill and prevent it from spreading by lining the ground with a tarp and damming the downhill flow with plastic blocks; (2) stop the acid leakage from the container, if possible; (3) soak up the acid already spilled by covering it with kitty litter; (4) collect the contaminated kitty litter for disposal; and (5) excavate contaminated soil if necessary (in this order). And she said never to use water or neutralizing agents to clean up concentrated acid in the field, because it can create sulfuric acid aerosol, which is extremely dangerous. 24.5.122.13 (talk) 09:45, 30 April 2014 (UTC)

Avalanche question

If an avalanche reaches a river, how likely is it that the debris and/or snow will form a debris dam and cause dangerous flooding? If this occurs, is the main hazard upstream or downstream of the dam? Thanks in advance! 24.5.122.13 (talk) 18:54, 26 April 2014 (UTC)

It happens - see Jan 27, 2014: Warm temps blamed for massive avalanche that cut off Alaskan town which says: "...some are worried that the large pool of water building up behind the avalanche could cause intense flooding". A Google search suggests that this is a relatively uncommon event, although that's probably not sound evidence. I discounted results that referred to rockfalls or landslides, often confusingly called "avalanches" in the press. In the UK, avalanches occur in high mountain gullies before rivers of any size have formed. However, in big mountain ranges where the avalanches reach enormous proportions, it is probably a different story. Alansplodge (talk) 20:00, 26 April 2014 (UTC)

I'm thinking Canadian Rockies, and the avalanche in question will be truly enormous, so it's definitely plausible. Thanks! 24.5.122.13 (talk) 20:17, 26 April 2014 (UTC)

It seems so. Apparently the town in the report that I linked to above, Valdez, Alaska, was saved from flooding because at least some of the water was able to drain away through a disused railway tunnel.[3] Alansplodge (talk) 20:32, 26 April 2014 (UTC)

The Mount Saint Helens eruption of 1980 was kind of the worst of both. A great amount of destructive debris and flooding downstream, and a greatly altered Spirit Lake created by the debris dam. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:13, 26 April 2014 (UTC)

• Our landslide dam article lists a number of examples. The main danger is downstream, because the debris dam would eventually break and the resulting downstream flood could be catastrophic. See 1786 Kangding-Luding earthquake for a particularly bad example (estimated 100,000 killed). See also our article on the 2010 Gansu mudslide, which dammed a river temporarily, although it was not caused by an earthquake. Looie496 (talk) 19:16, 27 April 2014 (UTC)

That's what I wanted to know. Thanks! 24.5.122.13 (talk) 23:14, 27 April 2014 (UTC)

I found a lot more examples of landslides causing this than avalanches, of which I could only find the one, which was only threatening. Alansplodge (talk) 01:39, 28 April 2014 (UTC)

Disaster reporting

In a mass-casualty disaster (such as an avalanche) with a final count of between 50-100 victims (dead, wounded and/or missing), how do the initial casualty reports typically compare with the final tally? Thanks in advance! 24.5.122.13 (talk) 18:59, 26 April 2014 (UTC)

Typically the initial reports of dead are very low, because they only count people when they find the bodies (also some wounded might later die of their injuries). The reports of the missing, on the other hand, tend to be high, because of all the people who fled the area or went to hospitals who are in the missing list initially. Wounded numbers could go up, if they find a batch of buried, wounded survivors. StuRat (talk) 20:08, 26 April 2014 (UTC)

(edit conflict) That makes sense, although in really remote areas, it can be much easier to estimate the number of people who might be in the affected area, and if relief is slow in arriving, the chances of finding survivors is small. See 8 April 2012: Kashmir avalanche: Up to 135 feared dead on Siachen, whereas our 2012 Siachen Glacier avalanche article gives a final death toll of 140, declared on 29 May. Alansplodge (talk) 20:24, 26 April 2014 (UTC)

So let's say all or most of them are initially listed as missing (as would probably be the case in an avalanche) -- would the initial number then be higher than the final tally, and how much higher? 24.5.122.13 (talk) 20:20, 26 April 2014 (UTC)

Well, the number of missing will go down, as people are found, whether dead, wounded, or unharmed. An exception would be if there was an unknown party of people in the area they discover are missing later, like a tour bus. StuRat (talk) 20:23, 26 April 2014 (UTC)

I managed to find February 24, 1999: Avalanche buries Austrian town "At least eight people have been killed after twin avalanches hit the small town of Galtuer in the Alps in western Austria. It is thought that more than 25 others are still trapped under snow...". Our 1999 Galtür Avalanche article says that "...in 24 hours the rescuers saved 26 people. The day after the avalanche, 31 people were confirmed dead". Alansplodge (talk) 20:51, 26 April 2014 (UTC)

The Lac-Mégantic derailment reporters called about 50 missing early. Forty-two were later confirmed dead and five presumed vaporized. Pretty close. InedibleHulk (talk) 21:59, 26 April 2014 (UTC)

• It's only a month since the 2014 Oso mudslide. The initial report listed 3 people dead and hundreds missing. The current report has 43 dead and 2 missing. Looie496 (talk) 19:32, 27 April 2014 (UTC)

Why do hyacinths stink?

A family member brought in some purple hyacinths, and boy oh boy do they stink up the whole house.

What is the point of hyacinths having a powerful enough stench to stink up the whole house? And how exactly is this stench produced? — Preceding unsigned comment added by 108.233.194.156 (talk) 21:35, 26 April 2014 (UTC)

They do that to attract pollinators, AFAIK. 24.5.122.13 (talk) 21:39, 26 April 2014 (UTC)

This aromatist may have some chemical answers for the how. InedibleHulk (talk) 22:06, 26 April 2014 (UTC)

I suppose it might also keep away animals that would eat them. StuRat (talk) 22:08, 26 April 2014 (UTC)

It sounds like OP is saying they smell bad. I don't believe hyacinths to have any kind of foul-smelling reputation (like the flowers of the callery pear or one of the carrion flowers). Do you just mean the smell is intense and off-putting because of its intensity? Like someone wearing too much perfume/cologne? --— Rhododendrites ^talk |  05:05, 27 April 2014 (UTC)

Yes. If it were maybe 1/1000 of the intensity, it might actually smell nice. — Preceding unsigned comment added by 108.233.194.156 (talk) 08:10, 27 April 2014 (UTC)

How plants, specifically flowers, produce scent is described here. The appreciation of some aromas, like that produced by hyacinths, is somewhat subjective. One man's stink is another man's perfume. Some hyacinths' odour is particularly potent and offensive to some noses. They "stink the place out" because they are brought into a closed environment. Take them outside and the problem will dissappear. I have serious doubts about the ability of the odour to deter consumers, I think it might have the opposite effect. It is worth remembering that the the intense odour is artificially produced, wild hyacinths have a perfume but far less intense. I agree with the earlier poster that plants naturally produce odiferous flowers to attract pollinators. Richard Avery (talk) 07:48, 27 April 2014 (UTC)