Surface area
hideSurface area is the measure of how much exposed area a solid object has, expressed in square units. Mathematical description of the surface area is considerably more involved then the definition of arc length of a curve. For polyhedra (objects with flat polygonal faces) the surface area is the sum of the areas of its faces. Smooth surfaces, such as a sphere, are assigned surface area using their representation as parametric surfaces. This definition of the surface area is based on methods of infinitesimal calculus and involves partial derivatives and double integration.
General definition of surface area was sought by Henri Lebesgue and Hermann Minkowski at the turn of the twentieth century. Their work led to the development of geometric measure theory which studies various notions of surface area for irregular objects of any dimension. An important example is the Minkowski content of a surface.
For more information about Surface area, read the full article at
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News tagged with surface area
Ego City: Cities organized like human brains
Sep 03, 2009 |
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(PhysOrg.com) -- Cities are organized like brains, and the evolution of cities mirrors the evolution of human and animal brains, according to a new study by researchers at Rensselaer Polytechnic Institute.
Get a grip! Blistering new evidence on why we have fingerprints
May 29, 2009 |
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(PhysOrg.com) -- Fingerprints do not help primates grip, as previously thought, scientists have discovered. They actually reduce the friction needed to hold onto flat surfaces. Now Dr Roland Ennos and his ...
One Sponge-Like Material, Three Different Applications
May 26, 2009 |
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(PhysOrg.com) -- A new sponge-like material that is black, brittle and freeze-dried (just like the ice cream astronauts eat) can pull off some pretty impressive feats. Designed by Northwestern University chemists, it can ...
Going platinum: New catalyst could boost cleaner fuel use
Nanotechnology / Nanomaterials
May 14, 2009 |
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(PhysOrg.com) -- Material scientists at Washington University in St. Louis have developed a technique for a bimetallic fuel cell catalyst that is efficient, robust and two to five times more effective than ...
Chemists create more efficient palladium fuel cell catalysts
Nanotechnology / Nanomaterials
Mar 19, 2009 |
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Even small devices need power, and much of that juice comes from fuel cells. As these devices become even smaller, the rush is on to find more efficient ways to power them.
Nanowires may lead to better fuel cells
Nanotechnology / Nanomaterials
Mar 11, 2009 |
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(PhysOrg.com) -- The creation of long platinum nanowires at the University of Rochester could soon lead to the development of commercially viable fuel cells.
New nanoporous material has highest surface area yet
Nanotechnology / Nanomaterials
Mar 09, 2009 |
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(PhysOrg.com) -- University of Michigan researchers have developed a nanoporous material with a surface area significantly higher than that of any other porous material reported to date.
Nanoparticle toxicity doesn't get wacky at the smallest sizes
Nanotechnology / Bio & Medicine
Feb 16, 2009 |
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(PhysOrg.com) -- The smallest nano-sized silica particles used in biomedicine and engineering likely won't cause unexpected biological responses due to their size, according to work presented today. The result should allay ...
Sex difference on spatial skill test linked to brain structure
Dec 17, 2008 |
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Men consistently outperform women on spatial tasks, including mental rotation, which is the ability to identify how a 3-D object would appear if rotated in space. Now, a University of Iowa study shows a connection between ...
Foam reactor is 10 times more energy efficient
Sep 26, 2008 |
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There is considerable worldwide demand for new types of reactors for the rapid and well- controlled production of high value chemicals. Charl Stemmet has developed the porous foam reactor, which has an energy efficiency ten ...
Scientists grow 'nanonets' able to snare added energy transfer
Nanotechnology / Nanomaterials
Sep 02, 2008 |
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Using two abundant and relatively inexpensive elements, Boston College chemists have produced nanonets, a flexible webbing of nano-scale wires that multiplies surface area critical to improving the performance ...
Turning Waste Material into Ethanol
Nanotechnology / Nanomaterials
Aug 13, 2008 |
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(PhysOrg.com) -- Say the word “biofuels” and most people think of grain ethanol and biodiesel. But there’s another, older technology called gasification that’s getting a new look from researchers at the U.S. ...
Research shows how insects use trapped oxygen to breathe underwater
Jul 30, 2008 |
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(PhysOrg.com) -- Hundreds of insect species spend much of their time underwater, where food may be more plentiful. MIT mathematicians have now figured out exactly how those insects breathe underwater.
