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Submission + - Scientists identify possible new substance with highest melting point

JoshuaZ writes: "Researchers from Brown University have tentatively identified an alloy of hafnium, nitrogen and carbon as having an expected melting point of about 7,460 degrees Fahrenheit (4120 Celsius). This exceeds the previous record breaker tantalum hafnium carbide which melts at 7,128 F (3942 C) and had stood as the record holder for almost a century. However, at this point, the record setter is still hypothetical, based on simulations. The new record has not yet been confirmed by experiment. http://journals.aps.org/prb/abstract/10.1103/PhysRevB.92.020104 is the actual article while http://www.washingtonpost.com/news/speaking-of-science/wp/2015/07/28/behold-a-new-record-for-the-worlds-highest-melting-point/ is a lay summary. If the simulations turn out to be correct, the new alloy may be useful in parts like jet engines, and the door will be opened to using similar simulations to search for substances with even higher melting points or with other exotic properties.

Comment Re:Lunar Space Elevator (Score 2) 48 48

I agree. Everything sounded reasonable up until I got to that point, and then I had to ask how much of what was above wasn't at all correct I was surprised about his statement that one might expect a lower cancer level in space from the lack of carcinogenic chemicals, and was thinking about that when I got to this point, and then updated with "oh, he just doesn't know what he's talking about."

Comment Re:I see theyre using the Step 2 profit model (Score 3, Informative) 188 188

Actually, replacing coal is happening already. The percentage of plants that are coal has been going down. Moreover, the plants which are coal have been getting progressively cleaner. And as electric-plugins become more common, that means there will be more on-grid storage which will help make solar and wind more common (since one of their big problems is the intermittent nature of the power they supply). Moreover, the study uses the current crop of electric cars, where they are getting more and more efficient, and as electric cars get more efficient they'll compare more favorably in more locations.

Comment Genetic situation (Score 1) 163 163

The actual genetic situation is substantially more complicated than your summary. Mitochondrial DNA indicates that Ashkenazic Jews (Jews from Eastern Europe) have a large influx of European women ancestors. See summary http://www.the-scientist.com/?articles.view/articleNo/37821/title/Genetic-Roots-of-the-Ashkenazi-Jews/. However, chromosomal DNA shows a major Middle Eastern component to the point where almost any Ashkenazic Jew is easily genetically distinguishable from a generic European http://scienceblogs.com/gnxp/2009/12/09/ashkenazi-jews-are-middle-east/. Moreover, around half of all Israeli Jews are not Askenaz but are rather descended from Sephardim and Mizrachim and the like (e.g. from Morocco, Spain, Iraq, Egypt, etc.) https://en.wikipedia.org/wiki/Demographics_of_Israel and have thus essentially zero European genetic ancestry.

Comment Re:The perfect is the enemy of the good. (Score 1) 139 139

Hmm? No, not at all. Note that the proposal here is a *proposal that is different from the status quo.* So claiming that this is some sort of attempt to keep the status quo doesn't work. So instead of trying to make what amount to unhelpful accusations about motivation, actually evaluate whether the policy would be a net improvement.

Comment The perfect is the enemy of the good. (Score 2) 139 139

The perfect is the enemy of the good. In the ideal universe all of this would be public already. But we don't live in that universe, and if we insist that all FOIA requests become available to everyone then overall fewer requests will be made. So the compromise proposed by the AC is the correct response, since it means that we'll have a small delay in the info getting public but it will actually get public.

Comment Re:Ozone layer is recovering (Score 5, Informative) 141 141

I can't tell if you are joking or serious, but I'll try to explain. The ozone layer is a completely distinct problem from global warming. The presence of ozone is necessary because ozone blocks UV radiation. Ozone does act as a weak greenhouse gas, as you can see on the list of greenhouse gases here https://en.wikipedia.org/wiki/Greenhouse_gas but it is one of the weakest. Note that if anything, this would mean you'd naively expect a lower temperature when there's more ozone (in fact the actual relation is more complicated). So the idea that the ozone hole would have caused warming is just deeply wrong.

Information is the inverse of entropy.