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Wikipedia:Reference desk/Archives/Science/2019 January 8

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January 8

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Need access to a scientific journal

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Hello. I write and edit science articles in Wikipedia, and there is one subject I want to update in the light of a new research paper, but the paper is behind a paywall. I wonder if Wikipedia has access to it on special bases. If so, which WP project may be doing this? The article and journal I need is:

  • Chlorate brines on Mars: Implications for the occurrence of liquid water and deliquescence. J. D. Toner, D. C. Earth and Planetary Science Letters, Volume 497, 1 September 2018, Pages 161-168. doi:10.1016/j.epsl.2018.06.011

Thank you, Rowan Forest (talk) 22:20, 7 January 2019 (UTC)[reply]

I'm not aware of any special access for WP, but sci-hub can pirate it if you're okay with that. Lusotitan (Talk | Contributions) 22:22, 7 January 2019 (UTC)[reply]
Actually, I don't need it any more. Thank you. Rowan Forest (talk) 22:32, 7 January 2019 (UTC)[reply]
You go to a library of a major University. They typically have electronic subscriptions for a host of scientific journals, show your credentials, talk to a nice young female librarian and she gives you an access to their computer and database. You must have a google email account. Thanks, - AboutFace 22 (talk) 23:20, 7 January 2019 (UTC)[reply]
For clarity: the Reference Desk endorses the use of proper channels to obtain permission for access to publications. We do not endorse piracy. We do not promote copyright infringement. Rather, we promote free access to free information.
Wnt, if you need an analogy to understand the difference: first, recall that there is a distinction between zero-cost and zero-restrictions. Imagine, by analogy, that you were queued in line to get some, shall we imagine, free beer; but while everyone else queued politely, you stand up, insisting that you're entitled to your free beer, that you don't respect anyone who pays for beer, and that you will take your beer with or without the permission of the people who are offering it to you at zero cost, because you admire piracy and renegade culture.
This would make you a boor, and it wouldn't really ingratiate you to all the people who are being nice, giving something away for zero cost, and the others who are all pleasantly partaking in an otherwise zero-cost exchange. I'm not sure where you are, geographically; but around my parts, boors can pay for their own beer.
Nimur (talk) 16:57, 8 January 2019 (UTC)[reply]
As I've explained here for me Sci-Hub has been the only practical way to get the research done on an article I'm revising right now. When submitted it's almost certain to be published given the Referee's comments. So, in the end, Elsevier itself is actually going to profit from Sci-Hub. And I'm working on a few other projects that I can only do thanks to Sci-Hub. Count Iblis (talk) 14:37, 9 January 2019 (UTC)[reply]
Nimur: I never heard of the Refdesk making "endorsements" of any kind. Nor was I even the first here to mention Sci-Hub; my role was to mention WP:WRE. I'm not sure if you're calling the people who run that boors also. The rest of your comment I don't get at all, though I suppose it's not about the NIH Public Access Policy. Wnt (talk) 23:57, 10 January 2019 (UTC)[reply]
My point, primarily, is that there are polite ways and there are impolite ways to get something for free. It is an official policy and a core value at Wikipedia: we prefer to use the polite way. Nimur (talk) 21:31, 14 January 2019 (UTC)[reply]
I'd like to politely encourage Alexandra Elbakyan to keep up the good fight. My core value would be more like "Imagine a world in which every single person on the planet is given free access to the sum of all human knowledge." Wnt (talk) 04:57, 15 January 2019 (UTC)[reply]

Strength of ice at colder temperatures?

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Can buildings like 30-stories be built on ice instead of steel or concrete at colder temperatures? For example, absolute zero is at -459 F, so imagine a city of ice buildings from -10 F to -100 F, all the way down to absolute zero. Can ice be strong enough? 67.175.224.138 (talk) 01:48, 8 January 2019 (UTC).[reply]

Icebergs can extend 75 meters above the sea, according to that article. Nine tenths of the iceberg is beneath the water, but I'm not sure this counts because of buoyancy (the compressive force does not increase below the waterline). Our article on ice hotels says that SnowCastle of Kemi is the largest and maxes out at 20 meters. Further cooling seems like a useful tactic, but I am hesitant to make any guesses about the engineering of what has never been built. Keeping a skyscraper standing is more complicated than just measuring compression strength. Ambitious people can plan remarkable accomplishments with what we think are limited materials -- see List of tallest wooden buildings for example. Wnt (talk) 03:25, 8 January 2019 (UTC)[reply]
Seriously, they even proposed turning an iceberg into an aircraft carrier! 2601:646:8A00:A0B3:940E:B215:E6AD:437C (talk) 03:35, 8 January 2019 (UTC)[reply]
The links you want there are for pykrete (a composite mixture of water ice and sawdust) and Project Habakkuk (the proposed aircraft carrier). Are we allowed to make an ice-based composite for the purposes of this question, or are we limited to the properties of pure water ice? TenOfAllTrades(talk) 03:44, 8 January 2019 (UTC)[reply]
Imagine a city with buildings on a foundation of ice which starts to melt. ←Baseball Bugs What's up, Doc? carrots→ 04:00, 8 January 2019 (UTC)[reply]
We don't really have to just imagine it—climate change is already making buildings at high latitudes vulnerable to melting permafrost. The linked article touches on some of the passive and active strategies used to attempt to avoid the worst effects, from insulation and passive ventilation through to installation of subsurface refrigeration systems. TenOfAllTrades(talk) 05:13, 8 January 2019 (UTC)[reply]
I think you've just effectively answered the OP's question. It's a No. It might work on Pluto, but not here. ←Baseball Bugs What's up, Doc? carrots→ 05:23, 8 January 2019 (UTC)[reply]
Well, not quite. The OP isn't asking if it's possible here on Earth. They're asking about the strength and suitability (for construction purposes) of ice at lower – and potentially regulated – temperatures. I took a quick stab at trying to answer that question by looking for data on the compressive strength of water ice under various conditions, but I was flooded (ahem) with data about natural ice at 'normal' Earth temperatures only.
And it's worth noting that as far as the (different) question you're answering goes, the source I linked to doesn't say we can't build on permafrost even here on Earth, it's just that it adds significant cost and complexity, e.g.
“The Arctic foundations are considerably more expensive in permafrost areas,” said Streletskiy. “For example, for large residential apartment buildings in Russia, the cost of the foundation can be as high as 30 percent of the structure.”
One hospital in Alaska went to extremes to make sure the ground would stay solid. The Yukon-Kuskokwim health facility in Bethel refrigerates the ground with temperature-controlled probes installed in the ground.
Unfortunately, none of that gets back to the original question about the physical strength of ice at very low temperatures. TenOfAllTrades(talk) 14:17, 8 January 2019 (UTC)[reply]
It would be interesting to dunk an ice cube into liquid nitrogen and see if it becomes brittle. — Preceding unsigned comment added by Baseball Bugs (talk • contribs) 15:35, 8 January 2019 (UTC)[reply]
Water-ice does not have an abrupt glass transition, the way many common materials do; so the ice won't behave significantly differently during such an experiment. The brittleness you often see when other items are chilled to very low temperature is not solely because of the cold temperature: it also depends on their material properties and in some cases their composite structure. Here are some notes for setting up a lab experiment, suitable for high-school or early college students, from Wright State University's college of engineering. Nimur (talk) 16:22, 8 January 2019 (UTC)[reply]
At conditions on the Earth, ice subject to stress flows in a glacier. But if the temperatures is much lower it becomes more rigid, eg on Pluto. Graeme Bartlett (talk) 09:50, 8 January 2019 (UTC)[reply]

This is an engineering question. So I don't think stuff like tensile strength for ice at colder temperatures is known. Imagine if there was a 20-story ice building at -50 F, and then the temperature is raised to 15 F (still below freezing) and then it would be interesting to see if the building would collapse. I'm also trying to find out about hydrogen peroxide as a solid. All the literature tends to be about it as a liquid (like density as a liquid) but no data like density as a solid. 67.175.224.138 (talk) 16:08, 8 January 2019 (UTC).[reply]

Anyways my question arises as a comparison - we know steel and concrete is strong enough to build skyscrapers - far below their melting point - and so therefore I wonder if something like ice can be just as tough also at far below its melting point. So I wonder if stuff like tensile strength gets stronger at colder temperatures? 67.175.224.138 (talk) 16:20, 8 January 2019 (UTC).[reply]
The trump question is, how do you keep it from melting? ←Baseball Bugs What's up, Doc? carrots→ 16:21, 8 January 2019 (UTC)[reply]
Water ice also suffers the unique property that it can melt (and deform!) at contact when under compressive load - which is very bad for structural integrity. The minutiae of these details are argued on an almost monthly basis in our article section on the physics of ice skating; but here's a reference from Physics Today: Why Is Ice Slippery? (2005). Water, and its crystalline ice state, are strange substances; the atypical relationship between density and temperature are the major reason why ice floats over liquid water, instead of sinking.
If you've been watching the news, you've surely seen the beautiful photographs of this year's Harbin International Ice and Snow Sculpture Festival; in Harbin, and in other places, artists sculpt and construct enormous building using ice, snow, and water (which then freezes). So, it is possible to build elaborate structures suitable for humans; but if you analyze this art with the bland rigor of a civil engineer, you'll see that the ice structures have poor performance for things like structural load, cantilever performance, and so on - even if we disregard concerns about melting. For many of the same reasons, we have the ability to construct homes and offices using sandbags, but we don't build many of those structures when other materials are readily available. When compared to these exotic alternatives, the cost and the structural limitations favor building with conventional materials.
On the other hand, a small niche of builders do use exotic material like ice (or earthworks); in some areas, the material is readily available; the aesthetic can be pleasing; and across the world, many ice hotels are both commercially viable and fascinating places to stay. It's unlikely, however, that we'll see permanent ice construction of tall megastructures, because there are better and safer construction materials to work with.
Nimur (talk) 16:29, 8 January 2019 (UTC)[reply]
St. Paul constructs buildings of ice every year about this time.[1] They're nice and sturdy. But they eventually melt. ←Baseball Bugs What's up, Doc? carrots→ 17:33, 8 January 2019 (UTC)[reply]
Ice it to brittle for construction houses. Parts under pressure may suddenly shatter without warning and cause everything connected to do the same. Maybe thats why no Inuit ever thought about a Building an Igloo with 2 or more stores. --Kharon (talk) 00:33, 10 January 2019 (UTC)[reply]
Igloos are not made of ice. --Guy Macon (talk) 15:18, 10 January 2019 (UTC)[reply]
Correct. Igloos are built from compacted snow. Nimur (talk) 17:41, 10 January 2019 (UTC)[reply]
 
Nevertheless, some fairly large ice structures are possible. catslash (talk) 01:23, 11 January 2019 (UTC)[reply]
If snow is not ice, which phase of water is it? --Jayron32 17:09, 11 January 2019 (UTC)[reply]
Something like a colloid of air and ice crystals which has different physical properties (like insulating ability) than ice alone (and segues into solid ice under places like Antarctica). Sagittarian Milky Way (talk) 17:49, 11 January 2019 (UTC)[reply]
So snow is a colloid? It's a aerogel? Look, I'm not that smart, but when I read the Wikipedia article titled "Snow", it states, and I quote "Snow refers to forms of ice crystals..." right at the beginning. If that is wrong, and it's actually some other phase of water, or some exotic colloid, you're going to have to change the Wikipedia article. Now, the second part of your statement, regarding its insulating ability, is true. But that is unrelated as to whether or not it is solid, liquid, or gas. It's still a frigging solid. You're confusing two very different facts, one of which has to do with the organization of water molecules into a particular phase of matter, and the other has to do with the bulk properties of snow verses some other form of ice. Words have meaning, and we need to use them correctly. Snow is ice. --Jayron32 18:42, 11 January 2019 (UTC)[reply]
Context matters. The comment I was replying to said "Ice is too brittle for construction houses. Parts under pressure may suddenly shatter without warning and cause everything connected to do the same. Maybe thats why no Inuit ever thought about a Building an Igloo with 2 or more stores." You may think that packed snow is the same thing as ice, but I seriously doubt that if you hit packed snow with a hammer it will shatter the way that ice will. --Guy Macon (talk) 20:46, 11 January 2019 (UTC)[reply]
I was responding to the statements that implied that snow was some phase of matter other than ice. Snow is ice, just small bits of ice with lots of air in between the small bits. The fact that, as small bits of ice with lots of air between the small bits, it has different properties than large blocks of ice is not in dispute. What is is that snow is somehow not ice. If you're proposing that it isn't, you're going to have to explain which of the other two states of matter it is. You've only got three to choose from, and if you're claiming it isn't one of them, I'd like to see which you claim it is. --Jayron32 21:36, 11 January 2019 (UTC)[reply]
No you weren't. You were not responding to any statement that implies that snow is some phase of matter other than ice. You were responding to (direct quote from the post you replied to) "Something like a colloid of air and ice crystals which has different physical properties (like insulating ability) than ice alone (and segues into solid ice under places like Antarctica)" (emphasis added). There is no substantive difference between "Something like a colloid of air and ice crystals" and "small bits of ice with lots of air in between the small bits". You are failing to carefully read the posts you reply to and thus end up mischaracterizing what was actually said. "A is B" is not the same statement as "A is something like B". --Guy Macon (talk) 16:27, 12 January 2019 (UTC)[reply]
This is very nearly off topic, but Jayron is right here. The difference between ice and snow is purely a matter of architecture. In this case it is mostly inadvertent naturally occurring microarchitecture, but of course, if you were actually going to make a thousand-foot skyscraper atop a cryovolcano on Enceladus, I dare say you might have a fancier snow making machine than an earthly ski resort uses in order to get formed elements of snow/ice/water aerogel/whatever you call it with just precisely the match of strength and weight you're looking for. Snow vs. (solid) ice illustrates part of the materials science aspect of this engineering project. Wnt (talk) 20:26, 12 January 2019 (UTC)[reply]
I should add that I actually looked up about igloos before ... the Inuit build them as temporary shelters for hunting, under conditions of survival (so they pile the blocks early and finish out under the shelter of them) which is presumably why they don't make them multiple stories. Wnt (talk) 20:31, 12 January 2019 (UTC)[reply]
Certainly Jayron is right that snow is a form of ice. But Guy is also correct that that point is a non-sequitur in context. I think probably Jayron didn't look back to see the full context, which is not a felony; we've all been there.
(By the way, Kharon didn't give a source, or even an argument, for the claim that Parts under pressure may suddenly shatter without warning and cause everything connected to do the same. I don't know whether that statement is accurate or not.) --Trovatore (talk) 21:31, 12 January 2019 (UTC)[reply]
This paper gives a useful abstract: "The mechanical properties of ice and snow are reviewed. The tensile strength of ice varies from 0.7–3.1 MPa and the compressive strength varies from 5–25 MPa over the temperature range −10°C to −20°C." It goes on to say that lower temperature increases compressive strength, while "The tensile strength of ice decreases with increasing ice grain size." I take from this the implication that even "solid ice" can vary substantially in organization, and also that the OP was right to think that lowering the temperature could help. Wnt (talk) 00:21, 13 January 2019 (UTC)[reply]
Like how an inch cube of (opaque) microcrystalline quartz should have different strength from an average inch cube cut from a quartz crystal so uncracked it's flawless under a 20x loupe and transparent? Sagittarian Milky Way (talk) 01:33, 13 January 2019 (UTC)[reply]
For that see fracture mechanics. Flaws lead to failure by fracture due to their tendency to concentrate stresses, so flawless material will always be stronger in either tension or compression. Mikenorton (talk) 18:29, 13 January 2019 (UTC)[reply]
I wouldn't say "always" -- see Strengthening mechanisms of materials, where flaws can be used to improve certain characteristics. SMW came up with a beautiful analogy, but honestly, I don't know which is stronger off the top of my head! Wnt (talk) 02:34, 14 January 2019 (UTC)[reply]
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