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+ - New recipe produces ammonia from air, water, and sunlight-> 1

Submitted by mdsolar
mdsolar (1045926) writes "Nitrogen is essential for all life. But even though nitrogen makes up 78% of the atmosphere, it's in a form that can't be used by living organisms. Instead it's tied up in nitrogen molecules made up of two nitrogen atoms that share a strong triple bond that's not easily broken. A century ago, two German chemists, Fritz Haber and Carl Bosch, figured out how to sever those bonds with high pressures and temperatures and weld nitrogen atoms with hydrogens to make ammonia, thereby converting nitrogen into the starting material for a nitrogen-rich fertilizer that can be taken up and used by microbes, plants, and people. That process has been so successful that ammonia-based fertilizers now enable farmers to feed billions more people than our planet could otherwise support. But ammonia production also comes at a high environmental cost, as it is responsible for 2% of worldwide energy use and thus a massive greenhouse gas footprint. However, on page 637 of this issue, U.S. chemists report that they've come up with a way to synthesize ammonia from air, water, and sunlight. If the approach can be scaled up, it could offer a means for making an essential commodity without a major cost to the climate."
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+ - Designers & Dragons is the complete history of role-playing game publishers

Submitted by Robotech_Master
Robotech_Master (14247) writes "Evil Hat Productions is Kickstarting a four-volume history of the RPG industry that's already met its funding goal almost seven times over. Comprising half a million words altogether, it tells the story of pencil-and-paper role-playing games from their very beginnings, and you can read the e-book of the first volume for kicking in just one buck. $1 for the first e-book, $15 for all four, print volumes starting at $25 and up.

I've reviewed the first volume of it here. I found it extremely thorough and well-written."

Comment: This needs to be seen (Score 2) 1

by Robotech_Master (#47377547) Attached to: Amazon vs Big Publishers - another side of the story

I feel it's really important that this piece get approved. The media is replete with Hachette, its authors and agents, and the various traditional publishing old-guard trying to stack the deck against Amazon. The other night the New York Public Library held a so-called "panel discussion" that was essentially an excuse to get together and bash Amazon. We need more people to hear the other side!

Comment: Re:Yes you are (Score 1) 634

by friedmud (#46964261) Attached to: Why Scientists Are Still Using FORTRAN in 2014

You can install PETSc without a Fortran compiler at all. Change that --download-f-blas-lapack to --download-c-blas-lapack and you're good to go...

In fact... MOOSE works on platforms without a Fortran compiler at all... although we generally recommend that you have one (so that you can still link in any legacy routines you've written in Fortran).

I'm not specifically against Fortran... I was just trying to say that most new computational science development at the National Labs is NOT being done in it. We've moved on...

Comment: Re:Because C and C++ multidimensional arrays suck (Score 0) 634

by friedmud (#46964221) Attached to: Why Scientists Are Still Using FORTRAN in 2014

Easily fixed with libraries like Eigen ( http://eigen.tuxfamily.org/ind... ) and many others.

Most of the better "frameworks" out there come with their own proxy objects for multidemensional arrays (like http://libmesh.sourceforge.net... )

Multidmensional arrays haven't been an issue (especially in C++) for quite a long time...

Comment: Re:We're Not (Score 5, Insightful) 634

by friedmud (#46964201) Attached to: Why Scientists Are Still Using FORTRAN in 2014

Firstly... 10^-15 is WAY beyond what most scientific codes care about. Most nonlinear finite-element codes generally shoot for convergence tolerances between 1e-5 and 1e-8. Most of the problems are just too hard (read: incredibly nonlinear) to solve to anything beyond that. Further, 1e-8 is generally WAY beyond the physical engineering parameters for the problem. Beyond that level we either can't measure the inputs, have uncertainty about material properties, can't perfectly represent the geometry, have discretization error etc., etc. Who cares if you can reproduce the exact same numbers down to 1e-15 when your inputs have uncertainty above 1e-3??

Secondly... lots of the best computational scientists in the world would disagree:

http://www.openfoam.org/docs/u...
http://libmesh.sourceforge.net...
http://www.dealii.org/
http://eigen.tuxfamily.org/ind...
http://trilinos.sandia.gov/

I could go on... but you're just VERY wrong... and there's no reason to spend more time on you...

Comment: Re:Why is anyone still using C++ in 2014? (Score 1) 634

by friedmud (#46964161) Attached to: Why Scientists Are Still Using FORTRAN in 2014

Not everyone needs to know all of the quirks of C++ to use it. My project ( http://mooseframework.org/ ) does all of the nasty C++ stuff under the hood so that we can expose a very straightforward interface to non-computer-scientists.

It's working out well so far.

Object-oriented is still a good paradigm until the functional language people get everything figured out and there are enough computational science libraries written in functional languages. And if you want to do object-oriented and you still want to be fairly close to the metal for performance reasons then C++ is a good choice.

There are people that do object-oriented with C like the PETSc team ( http://www.mcs.anl.gov/petsc/ )... and they have good reasons for doing so... but the result isn't necessarily less imposing to the uninitiated than C++...

Comment: We're Not (Score 1, Interesting) 634

by friedmud (#46964121) Attached to: Why Scientists Are Still Using FORTRAN in 2014

I saw this link bait the other day...

We're NOT using Fortran anymore...

Many of us at the National Labs do modern, object-oriented C/C++... Like the project I'm in charge of: http://www.mooseframework.org/

There are whole labs that have completely expunged Fortran in favor of C++... Like Sandia (http://trilinos.sandia.gov) who actually went through a period in the late 90s and early 2000s where they systematically replaced all of their largest Fortan computational science codes with C++.

Those places that don't use C++ use C like the awesome PETSc library from Argonne ( http://www.mcs.anl.gov/petsc/ ) which actually employs an object-oriented scheme in C.

The big name modern codes that are getting run on the biggest machines are generally done in C and C++.

I don't see that situation changing anytime soon as there is simply a massive amount of C and C++ libraries that will continue to provide the engine for tomorrows codes. The trend i see happening most often is utilizing C and C++ libraries with Python glue for everything doesn't need raw speed.... I think that trend will continue.

"An open mind has but one disadvantage: it collects dirt." -- a saying at RPI

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