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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:No Compromises (Score 1) 139 139

The lack of NFC is disappointing.

If you're not planning to use your cell phone also as a Credit Card...then what other uses really are for NFC?

I'd not want any of my CC info on a phone that can be stolen and cracked into. And from the article, apparently not that many people out there are even using NFC functionality, so I'm guessing to many it is no great loss.

What all do you use NFC for so much that it is a deal breaker for you? Seriously curious.

Thanks!

Comment Re:Blimey (Score 1) 443 443

I had to look deeper to see that you are correct. There _have_ been several NASA published designs using microwaves or other EM for ordinary thrust, I'm afraid I thought the original article concerned one of those.

On review, as I mentioned elsewhere, I'll bet that this is really a "Dean Drive". The Dean Drive never worked well outside the designer's workshop, was never tested properly with a basic "pendulum" test, and seems to have been a basic "oscillation thruster": it interacted with the floor under it to provide net thrust. That would mean the system is not really "sealed", it's interacting with its environment in some subtle way.

From the description at http://motherboard.vice.com/re..., I'd guess EM interaction with the walls of the stainless steel vacuum chamber. And one of hte people I'd want to review the experiment would be James Randi, who's been helping debunk "mysterious mental force" claims for decades, and has a professional magician's eye for misdirection and sleight of hand.

Comment Re:The argument is "leaky" at best too (Score 1) 190 190

> evolution does not consider risks and benefits, changes are random

Interestingly, not all changes are random. There are some fascinating changes in DNA triggered by environment, many of them studied as "epigenetics". And there are certainly changes in organisms that are defensive responses to environment. The darkening of skin under sunlight is a classic example. Evolution occurs at _many_ levels. These include environmental, biological, behavioral, cultural.

Comment Re:Not the best summary... (Score 5, Insightful) 190 190

> The only group that is really helped by other people's vaccinations is a small percentage of the population that cannot get vaccinated.

You obviously don't remember polio. I do. You apparently also don't remember when the flu killed so many people in winter, and fail to understand how modern cities and especially air traffic make pandemics far more likely and far more dangerous.

Comment Re:But... but? (Score 2) 164 164

I don't have any problem with the account verification though - it's just a variant of the 2-factor authentication so don't complain too much, it may prevent you from getting your account hijacked.

Well, I just would rather not give Google my cell phone number...

Comment The Dean Drive is back (Score 2) 443 443

There was a similar set of claims roughly 60 years ago for the "Dean Drive" a "reactionless drive" that did not seem to use propellant. To casual review, and letting it push your hand, it seemed to work, and a great campaign for research and to ignore the sceptics of the time was headed by John W. Campbell, the editor of Analog magazine. Analog was, and remains, a science fiction magazine specializing in hard science and science fiction based on it, and it had many real scientists as readers and contributors, so the Dean Drive received quite a lot of attention.

The Dean Drive has since been pretty thoroughly debunked as an "oscillation thruster", a device that relies on tuned "slipping" on the floor it rests on to creep forward and even to provide a modest thrust, _pushing against the floor_. The designer was never willing to allow a full "pendulum" test, or careful testing outside of his own workshop, and there seem to be dozens more of similarly patented "reactonless drives". The ones that work at all also seem to be "isicllation thrusters", pushing against the floor or the mehanism in which they are mounted.

Comment Re:Blimey (Score 1) 443 443

> As an added added bonus, such a drive would accelerate faster at a given thrust, because of the absence of reaction mass.

If only they didn't require an actual motor, or storage system for the energy for the microwaves. Since the maximum _chemical_ energy available in batteries is quite close to that of a good chemical propellant, it's only a big benefit if the energy for it comes from elsewhere, such as solar cells or a quite large nuclear power source. And if you have low mass space based solar cells, you can use either a solar _sail_ based system, or a transmission base to propel target spacecraft with a larger, more stable microwave source.

The brain is a wonderful organ; it starts working the moment you get up in the morning, and does not stop until you get to work.

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