Talk:Stainless steel

Again: How is Stainless Steel Made?

This article contains lots of information about various alloys, but NOTHING about how stainless steel is cast, poured, machined, whatever. It's only half the story!

How is the chromium added to the iron? Can it be cooled in the open air? Remelted?

Come on, guys!68.111.71.197 (talk) 23:05, 29 November 2008 (UTC)

It's made just like any other steel. Stainless steel is essentially just a special type of alloy steel. 131.151.161.156 (talk) 09:50, 11 February 2012 (UTC)

melting temperatures and electrical conductivity

Please add melting temperatures and electrical conductivity. -71.174.182.182 (talk) 13:12, 21 May 2009 (UTC)

give the types of ss and melting points —Preceding unsigned comment added by 61.17.10.66 (talk) 08:06, 12 January 2010 (UTC)

Adding such basic information as the melting temperature in any article on a metal is important. — Preceding unsigned comment added by 98.166.255.47 (talk) 13:54, 19 March 2012 (UTC)

Stainless chair

I would like to commend whomever it was that found/posted that chair photo on the beach showing that magnificent specimen in demonstration of the corrosion resistance of stainless steel. Subjecting that specimen to a wet and salty enviroment is a perfect illustration of an environment in which you would very much prefer to have stainless steel. Is there some way to move that the author be credited with some kind of wiki award? 63.71.19.253 (talk) 19:10, 22 February 2010 (UTC) Koozie, Chemical and Materials Specialist.

Thanks too much by the praise. Its our work. Made in Brazil. You know... Beautifull places, amazing woman here. —Preceding unsigned comment added by Alex Rio Brazil (talk • contribs) 03:25, 23 February 2010 (UTC)

Be that as it may, the picture isn't suitable to demonstrate the subject matter - the focus is not on the chair but on the model. Alex, feel free to take another photo of the chair without the model posing on it, as this would be great material for the article. If people feel an image of a Stainless Steel chair is really necessary for the article, a suitable one can be found - in the meantime i see no reason to make an encyclopaedic article into content that would often be considered "not safe for work". Also, addidng random examples of things that can be or are made of stainless steel adds nothing, the article already makes it clear that it's a useful metal. Image removed on that basis. Provider uk (talk) 19:44, 21 April 2010 (UTC)

"Not safe for work" ? Where? What kind of workplace is *that* uptight, yet still has the Internet (and electricity)? Wikipedia is not censored, and the picture depicts someone appropriately dressed for the seashore using a stainless-steel object especialy adapted to that corrosive environment. I think the picture is completely fit and appropriate for the topic,but I have seen other cases where perfectly suitable pictures have been tossed out of articles. --Wtshymanski (talk) 21:05, 21 April 2010 (UTC)

What chair? ... oh, there is a chair in that pic! :) Vsmith (talk) 21:09, 21 April 2010 (UTC)

The model provides scale, to clarify how large the furniture is in relation to a typical human. Without the model, something like a meter stick would be required, and might be harder to find at the beach. The site helps to emphasize the corrosion resistant properties of stainless steel. In what sort of workplaces are images of females prohibited? Edison (talk) 21:36, 21 April 2010 (UTC)

In most workplaces i've been in, wikipedia would construe reasonable reference material, but any image like the one used would immediately cause anyone looking to assume it was not reference material being consulted. Given that this doesn't have to be the case (there are many other images that would suffice that would not arouse the same controversy) I really don't see why it needs to be here. If i can find another picture that shows the relative scale of a person and a chair (really? This seems a little facetious to me - the article isn't about chairs or the scale thereof but if that's what it takes then so be it...) would the change be accepted? An encyclopedia wouldn't use an image like this, we don't need to either. I also refer you to Queued_images#Content "Images should depict their content well (the object of the image should be clear and central)." This image would appear not to fall into this category. It's also very low resolution and the chair is somewhat out of focus. Vsmith's comment above, tongue in cheek or not, makes it obvious that this image does a poor job of representing the (article's) subject matter. Provider uk (talk) 00:14, 22 April 2010 (UTC)

While we're on the subject, it's actually just (badly) concealed advertising for the company that makes the chairs, which is what i picked up on in the first place. Provider uk (talk) 00:19, 22 April 2010 (UTC)

I gotta say I see people DRESSED less "work appropirate" than that at work nvm looking at pictures, and I work in locations that have dress codes.--174.45.157.36 (talk) 00:34, 22 April 2010 (UTC)

Any magazine of general circulation, like Time or Newsweek regularly includes women in swimwear. This is not Conservapedia. Arguing that the photo promotes a particular manufacturer of chairs is an argument that makes more sense, but it would equally rule out other photos of things made by some company, thereby eliminating a large portion of the illustrations. No name brand is visible on the chair, so it does not appear promotional. It shows a stainless chair in a setting where a tubular steel chair would quickly oxidize (not sure about aluminum) and a wood chair would be likely to rot. Wikipedia is not censored to prevent someone seeing you looking at an article on stainless which includes a model in a swimsuit sitting in a chair with a stainless frame. It illustrates that tubular stainless is ductile, strong, and attractive and suggests that it is corrosion resistant. Wikipedia is an encyclopedia which has a great many articles which would not be safe for your workplace. If you find it generally unacceptable on grounds of being titillating, I suggest you try adding [[File:Stainless Steel chair with yellow plastic in Rio de Janeiro Sea.jpg]]to the "bad image list" found at MediaWiki:Bad image list. (Do not under any circumstances look at any of those images at your workplace.) Edison (talk) 02:49, 22 April 2010 (UTC)

I'm in no way suggesting it needs to be censored, simply that it's not a good image to illustrate the point, due to the fact that there's a person obscuring the chair, and taking up a large portion of the photo. It also appears to have distracted the photographer from his task - as i mentioned above the woman in better focus than the chair is. This is an encyclopaedia not a newspaper - they include such images due to the commercial reality of having to appeal to as wide an audience as possible - we are not subject to such unpleasant constraints. An encyclopaedia would not use such an image to illustrate an article on stainless steel. My point about workplaces is that someone coming here for reference would be forced to scroll the image off the page if a supervisor approached - looking at such images in work time is not normally considered acceptable. Much like reading the newspaper or magazine - it's a recreational activity, no? Provider uk (talk) 20:49, 22 April 2010 (UTC)

I should also point out that as far as i can ascertain the "ANSI 304" stainless steel referred to is standard grade stainless, and completely unsuitable for long-term salt-water use. Regarding advertising - what we have here is a promotional shot of a model posing next to a chair, with a link to the company that produces the chair on the image page. It's advertising of a fairly blatant nature that also misrepresents the capabilities of the product Provider uk (talk) 20:55, 22 April 2010 (UTC)

Marine_grade_stainless —Preceding unsigned comment added by Provider uk (talk • contribs) 20:57, 22 April 2010 (UTC)

Well... No one is saying that AISI 304 is for long term salt usage. Its just saying that you can get it into the beach with no harm to the material. If you think that the sentence is ambigous feel free to do an improvement. I think that this is not conservapedia and we must make the articles atractive for people in general, i must make knowlegde an interested thing capable to atrack more people and not only a few initiated ones. This picture, as the others, make the text more brillant. People like practical use like this, like me or you do in our daily life, not any piece of metal, but a recognizable one.Alex Rio Brazil (talk) 16:19, 25 April 2010 (UTC)

In any case, the picture has been recently removed by an anonymous user (not me). --92.81.3.135 (talk) 12:22, 4 July 2010 (UTC)

Obviously there is someone who is adamant about keeping this useless picture on the page. It adds no value to the discussion of stainless steel, and to use it as an attention grabber is not only misguided but an example of sexist motivation in advertising. Alex Rio argues that the picture makes the article more attractive; this is an encyclopedia article, not USA Today. Who does it make it attractive to? Not any women reading the article, that's for sure. And there's already pictures of some fabulous stainless steel art on the page. Irregardless, this article doesn't strive to attract random and numerous viewers, it is here as an educational resource. A woman in a bikini is not informative or educational, just another attempt by a man to objectify women in whatever context possible. Leave this picture out of the article and let those who want to see those kind of images go to the porn star pages on Wikipedia or other sites entirely. There is absolutely no essential purpose it fulfills, and the article loses nothing when it's removed. By the way, I have no Wikipedia account but my name is Stefan and I'm an adult male in Minnesota, USA. 69.54.33.62 (talk) 17:55, 21 March 2011 (UTC)

In short, Wikipedia:IDONTLIKEIT. --Wtshymanski (talk) 18:11, 21 March 2011 (UTC)

You consistently restore this image because of "consensus" on the talk page? I see no consensus. It seems more people are attempting to remove it than restore it. My issue with the picture is it is about 3% stainless steel and 97% woman. When I saw the picture, I thought "why is a woman in a bikini on this article? Oh, she is sitting on a chair with some stainless steel on it." It is distracting, and takes away from the point of the picture and the article. She is even posing; the emphasis is clearly on her, not the chair. I will not remove the picture immediately, but I strongly recommend doing so. I see no good reason why it should be included in this article.Enigmocracy (talk) 04:44, 30 March 2011 (UTC)

It's incredible how quickly an argument will be dismissed by a male-dominated population when it includes mentions of sexual objectification. Give me a real reason that this picture, out of all the picture of stainless steel art and products, should continue to exist on this page. Why not a picture of a steel dildo or steel genital piercing? How about a male model instead? Does the article suffer without this random picture of a random female model of a random chair? My personal aversion to sex in advertising does not justify the continued inclusion of this picture; it is only being re-posted in defiance by someone who is unwilling to argue for why it should exist. It has no purpose in this page, and distracts significantly from the actual subject matter. Just look at the beginning of this discussion page. There's no one saying "what a great make of chair, what a fantastic example of steel construction." The focus is on the woman, some men celebrating her and some saying it's pointless. Obviously the picture has nothing to do with stainless steel. 69.54.33.62 (talk) 18:28, 21 March 2011 (UTC)

But it's a stainless steel chair? Oh my. I had no idea a picture of a pretty girl in a chair lead inexorably to steel dildoes and genital piercing; certainly not on the same track as my train of thought, anyway. Wikipedia content discussions sometimes give a fascinating glimpse of how others think. We should perhaps remove all people pictures from the Wikipedia for safety, since at least one major world religion prohibits making of human likenesses, and we dare not offend anyone. One can "defy" authority; one only reverts edits on the Wikipedia. --Wtshymanski (talk) 18:49, 21 March 2011 (UTC)

Let me provide a few examples. Look at the article for chair. In not one of those pictures is a person spotted. That's because it isn't an article about people, it's an article about chairs, and too many pictures of people would distract from the point, unless it was an object whose understanding relies on a person being in it, e.g. baseball bat. This isn't about sexism or objectification, it's a very simple matter of Wikipedia:Images#Image_choice_and_placement For other examples of articles on plain objects, look at Desk, Pencil, Table, Couch, and so on. It is *clearly* the accepted convention, for the same reasons I have explained, to use pictures of objects where the *object* is the focus, not a person next to it. I am surprised this picture has remained for so long.Enigmocracy (talk) 04:52, 30 March 2011 (UTC)

Showing human artifacts in use by humans would seem to be appropriate. --Wtshymanski (talk) 13:59, 30 March 2011 (UTC)

By your logic, *all* objects should have pictures of people using them, which is *clearly* A. Distracting and B. against Wikipedian standards.Enigmocracy (talk) 21:07, 30 March 2011 (UTC)

Just throwing my two cents in, but I think the image ought to go, because the focus is wrong. Wizard191 (talk) 01:37, 31 March 2011 (UTC)

OK, I've consulted the talk page again, I remain unimpressed by the argument for deletion of the picture, and I look forward to its restoration. --Wtshymanski (talk) 21:33, 1 April 2011 (UTC)

I gathered that from your restoration of the image. Do you mind explaining why you insist on having this picture in this article despite the fact that:

1. The chair is *clearly* not the focus of the image. I encourage you to show that picture to anyone (and not just those who would find her attractive) and ask whether the first thing and the primary thing they notice is the stainless steel chair is the focus of the image. She is a model, she is *posing* for the camera. This isn't about the chair, it is about her. Per Wikipedia:Images#Image_choice_and_placement, images should focus *on* the object in question, not on anything else. 2. This is not a precedent set *anywhere* in Wikipedia articles, for the reasons I explained above. Point to one article, or one encyclopedic-quality source which uses a posing model in a bathing suit to emphasize the object in question.

I have currently replaced the picture with a more generic picture of a stainless steel chair. I will not make any further edits until a consensus has been reached, but this seems like a fair compromise to me.Enigmocracy (talk) 01:01, 2 April 2011 (UTC)

OK, I've consulted the talk page again, I remain unimpressed by the argument for deletion of the picture. We have to put more content, insted of deleting it. There is no profit in it. 187.13.112.5 (talk) 23:13, 1 April 2011 (UTC)

More content is not always better, especially when the content is unhelpful and distracting.Enigmocracy (talk) 01:01, 2 April 2011 (UTC)

Unhelpful and distracting is your oppinnion that is not shared by people involved here. If there is no clear rule saying that the girl's picture must be out, so, it must be in.Alex Rio Brazil (talk) 13:13, 2 April 2011 (UTC)

If by "people", you mean Wtshymanski and yourself, you are correct. Please answer my this question: Why is the picture with the girl preferable to the one I posted without the girl? I have given you several disadvantageous, and as evident earlier in the discussion, I am not alone in sharing these opinions. We will never come to a consensus if you do not make coherent arguments as to why this picture is BETTER than the one that I posted. By your logic, there is no clear rule as to why the plain picture of a chair should be out, so it should also be in. We are back to square 1.Enigmocracy (talk) 14:01, 2 April 2011 (UTC)

I agree with enigmocracy. This picture is clearly not encyclopedic material and is inappropriate for this article.Mvp15 (talk) 14:15, 2 April 2011 (UTC)

Why is the picture with the girl preferable to the one I posted without the girl? The question is not why. The question is why not? The girl picture was choosed by the colaborator, so, there must be maintened once it dosent violate no clear rule. —Preceding unsigned comment added by 187.13.112.5 (talk) 14:33, 8 April 2011 (UTC)

Just because an image or textual content doesn't break a rule doesn't automatically make it the best choice. In this case, both images suck and there are plenty of better images of stainless steel in the article already. Otherwise check out commons:Category:Stainless steel for even more images that are better than these two chairs. Wizard191 (talk) 15:38, 8 April 2011 (UTC)

I agree with this action. I only added the black chair picture because my attempts to remove the other image entirely were constantly being reverted.Enigmocracy (talk) 22:23, 8 April 2011 (UTC)

Better? Who decides what is better? To me and many others this one with the girl is the better one. If you dont work. Dont try to stop the ones who does it. —Preceding unsigned comment added by 187.13.55.21 (talk) 18:53, 28 April 2011 (UTC)

I think it's pretty universal that this image sucks as an example of stainless steel. If you take a percentage of pixels used to depict the stainless steel vs. the pixels to depict everything else minus the pixels used to depict white space, the percentage is tiny. As such, if there is consensus that another image is even needed as an example of stainless steel, of where I don't think there is a need, then a better image needs to be selected. Wizard191 (talk) 20:15, 28 April 2011 (UTC)

Activation of stainless steel

Stainless steel may be activated, e.g. the protective Cr2O3 coating removed, by acids. When a stainless steel screw is placed in concentrated hydrochloric acid, it corrodes to form hydrogen gas and a mixture of chromium chloride, nickel chloride, and iron III chloride. Also, when stainless steel is placed in concentrated copper II chloride, the Cr2O3 coating is dissolved by it, reforms, dissolves, reforms, dissolves, etc..., leaving a chromium oxide precipitate. Meanwhile, the iron is corroded also. Activated stainless steel, according to the galvanic series of metals in seawater, is only slightly less active than ordinary iron. --Cheminterest (talk) 20:53, 12 March 2010 (UTC)

Well yes, of course if you strip off the Cr2O3 layer in an oxygen deprived environment it corrodes just like ordinary iron! The whole point of stainless steel is forming that protective chromium oxide layer. Oh, and your comment isn't actually quite true - the nickel additions in austenitic stainless will still reduce corrosion. 131.151.161.156 (talk) 09:34, 11 February 2012 (UTC)

here no one discuss about the super austenitic steel and there color docing system as per standard.(kashif bin nazir) —Preceding unsigned comment added by 198.36.39.4 (talk) 08:13, 2 May 2011 (UTC)

Health effects?

I didn't see any mention of adverse effects of the large chromium content.

While chromium oxide is obviously inert and therefore non-harmful, the same cannot be said of chromium salts, which are all far more poisonous (especially in its hexavalent form) than those of iron. If cooking in stainless steel cookware can disturb the protective coating (such as by those foods which are acidic), wouldn't it be possible for chromium chloride, chromium acetate chromium carbonate, chromium sulfate, and other such soluble salts to form and dissolve in the cooking water? Note that there seem to be no published studies on the health effects of chromium compounds on children. Hot stainless steel (such as occurs during its manufacture and during welding and brazing operations probably releases fumes that are not very healthful. The salts of nickel are also not the happiest to ingest. I'm just raising these questions so they can be used by someone in the future who would like to do some research. Web searching seems to raise questions like these, but not to present real evidence of harmlessness. David Spector (talk) 00:06, 22 August 2010 (UTC)

The chromium on the surface is caught up in an oxide, not a soluble salt - if the chromium dissolved in any significant way, it wouldn't be much good for protecting steel. It's also in the +3 state - the toxic form is hexavalent (+6) chromium, so even if some got chipped off and ended up in food it wouldn't be an issue. The nickel isn't any more toxic than nickel jewelry, especially since it's only around 8% of the material (and only austenitic ones) - I doubt even those allergic to nickel would notice, since the nickel doesn't participate in the formation of the passivation layer.131.151.161.156 (talk) 09:46, 11 February 2012 (UTC)

Oxidation Process in Stainless Steels

What is the Oxidation Process in Stainless Steel please give me the scientific explanation. —Preceding unsigned comment added by 122.182.4.178 (talk) 09:09, 17 January 2011 (UTC)

"Inox" etymology

At the head of the article the following derivation is given for the term "inox": "also known as inox steel or inox from French "inoxydable", coming from the Latin words in and obsidium (siege, blockade)". I wonder what the source is for this. I have always understood "inoxydable" to mean "unable to be oxidised", or in the case of iron or steel, "unable to rust". The term would have been coined by a chemist or a metallurgist, and, as a description of stainless steel, I would have expected it to have been directly from the French term for oxidation. Does anyone know why the derivation above was given instead? AFBankier (talk) 06:26, 30 May 2011 (UTC)

I just read this comment (2011-12-16), and I note that the article no longer talks about any siege/blockade etymology. Which is good, because I agree that it sounds mistaken. No one ever told me that "inox" means "not oxidizable", but I figured it out on my own, and I suspect that lots of other people have, too. I strongly doubt that the true etymology is anything more fanciful than in- ["not"] + oxy ["oxygen", "oxidation"]. Prove me wrong, world. — ¾-10 00:34, 17 December 2011 (UTC)

"Natural stainless steel"?

It is apparently "almost impossible" to tell the fall date of a Nickel_iron_meteorite from the meteorite itself because it is very resistant to atmospheric corrosion. Could this, therefore, reasonably be called a "natural" form of stainless steel? IF not, why not? Old_Wombat (talk) 10:21, 14 December 2011 (UTC)

I suppose that the answer depends on who you ask, because it depends on their judgment of "reasonably". If you ask me, yup, it's reasonable. BTW, one thing this makes me wonder is where is the dividing line of iron content where nickel alloys cease being considered "nickel-alloy steel" and are not "steel" anymore, even if they do contain some iron (but not "enough" to be called "alloy steel"). I'd bet that materials-sci-&-engr type people have a good, quantitative, arbitrary, operational answer to that (>X% Fe vs <X% Fe). Anyone here know? — ¾-10 00:44, 17 December 2011 (UTC)

If it can be cited that someone calls meteorites "natural stainless steel", then we can cite it. I suspect the nickel content is too high and the carbon content too low to be considered a "steel" of any kind. --Wtshymanski (talk) 18:47, 17 December 2011 (UTC)

Looks like one fore and one against LOL. Wtshymanski, where I am coming from is this. Nickel-Iron meteorites are found literally lying all over the world. Many of them have lain there for hundreds or thousands (or even hundreds of thousands of years), yet many of them are still shiny and unrusted, or, at worst, have only a thin rust coating. They have outlasted all and any man-made stainless steels. So irrespective of any formal definition of "stainless" or even "steel", I feel that they are worth mentioning. The entire point here is that a nickel-iron alloy, even if not man-made under controlled conditions and to a precise recipe, can resist corrosion (rusting) for timeframes in the geological scale.

How about we change tack on the whole matter? I have a proposed paragraph for inclusion. Rather than have an abstract debate, we can concentrate on whether to include it at all, and if so, in what form. So here we go:

Iron meteorites, which are made almost entirely of nickel-iron alloy, are found almost completely unrusted, despite having lain out in the open for, in some cases, many thousands of years (for example, the Hoba meteorite). This is far longer than any man-made stainless steels have survived. Whilst they are a naturally occurring nickel-iron alloy, whether they can be formally considered as a "natural stainless steel" is, however, open to debate.

Please attack at will. Old_Wombat (talk) 07:12, 23 December 2011 (UTC)

I think it is a pointless diversion to add to this article unless we can find reliable sources calling meteorites "natural stainless steel". The analysis of a meteorite does not resemble that of steel. --Wtshymanski (talk) 15:06, 23 December 2011 (UTC)

The Hoba meteorite article doesn't say it has any carbon content at all. "No carbon" excludes this substance from the class of steels. --Wtshymanski (talk) 15:14, 23 December 2011 (UTC)

OK, we are not seeing each other's POV at all, so it is pointless to continue. Old_Wombat (talk) 04:51, 26 December 2011 (UTC)

I think speaking about certain facts of nickel iron meteorites to illustrate the corrosion resistant ability of nickel alloying could be an asset to a nickel or iron-nickel alloy page (it's also just generally interesting.). I wouldn't go so far as to classify it as a 'stainless' steel, unless we can verify specifics on chemical composition.

Unispehere largest globe shaped structure... No

The Stockholm Globe arena is 110 meters in diameter rather than the ~37 meters of the Unisphere, therefor the argument previously posted that the Unisphere should be the worlds largest globe shaped structure is not true. I deleted this info and added info about the Unisphere's size instead. — Preceding unsigned comment added by 138.106.53.11 (talk) 09:50, 27 January 2012 (UTC)

Remarks on entry

First, Leon Guillet from what I read, is the first person to make detailed studies of both the 400 and the 300 series steels, and is considered the "father" of stainless steels. Thus he should get more mention in this entry.

Additionally, it is written that in 1912, the Krupp company patented the first 300 series steel, under the name Nirosta. I checked the reference, and it only mentions they had some stainless steel, not necessarily the 300 series austentic steel. And this demands proper referencing. — Preceding unsigned comment added by 31.210.180.107 (talk) 14:48, 24 April 2012 (UTC)

taken down

Anyone knows why the link to www.renaissancegroup.co.in was taken down? Is there a rule against sites like mine? — Preceding unsigned comment added by 114.143.31.59 (talk) 14:14, 29 June 2012 (UTC)

References

Reference 1 on this page does not open the proper PDF. It appears the hosting site has changed the location and content somewhat. The correct pointer is http://www.worldstainless.org/news/show/90 Drrichs (talk) 09:21, 12 November 2012 (UTC)

Applications for Ferritic Stainless Steel

This article omits to tell us what uses are made of Ferritic Stainless Steel. It would be useful if someone in the know would add this missing information. Thanks. FreeFlow99 (talk) 21:33, 1 April 2013 (UTC)

Error in navbox: "Iron-carbon alloy phases"

"Graphite (allotrope of carbon)" is an erroneous element of the navbox in the article:

The element is totally incorrect in the navbox called "Iron-carbon alloy phases", i.e.: "Graphite (allotrope of carbon)" is wrong because Graphite (formula = C) is not a phase of steel alloy, as graphite is pure carbon, not of any relevance to stainless steel. Garshepp (talk) 03:36, 6 April 2013 (UTC)

chemical composition %ages

Noted value of 13% Chromium content for stainless steel. I've formed martinsitic specimens with the addition of only 10.5% Cr and up to 1%C, ferritic specimens can form at 11-27% Cr., 0.2%C maximum.

Suggest range value from 10.5% to 25%+ (or the value at which it is considered high alloy stainless) and explanation of range and alloying contents for different specimens (ie ferritic, martinsitic, austenitic). not my goal to start an argument, just desire to set a range rather than a single value and misdirect people into believing 13% is the low end.

Displaying compositions with a table would probably be the most expedient.

sources: ASM/AWS materials handbooks, (most available for viewing via google scholar if you don't believe me) and my instructor who is a 20 year metallurgical engineer, also a 2nd year materials engineer. 70.72.163.161 (talk) 17:50, 18 April 2013 (UTC)