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Someday We Will All Be Cyborgs

Written by The Naib

I am convinced that one day everyone will have some sort of “enhancement” be it better knee joints, sharper vision, better hearing, or like this awesome guy new legs that let you do things your old legs never could.

I see these sort of stories as some of the best proof out there that science has the potential to make our lives better.

If You Live In South Dakota Check Your Horoscope

Written by The Naib

Seems that the good law makers of South Dakota now believe that global warming could be caused by astrology…

By a 36-30 vote, the legislators passed House Concurrent Resolution 1009,

NOW, THEREFORE, BE IT RESOLVED, by the House of Representatives of the Eighty-fifth Legislature of the State of South Dakota, the Senate concurring therein, that the South Dakota Legislature urges that instruction in the public schools relating to global warming include the following:

(1) That global warming is a scientific theory rather than a proven fact;
(2) That there are a variety of climatological, meteorological, astrological, thermological, cosmological, and ecological dynamics that can effect [sic] world weather phenomena and that the significance and interrelativity of these factors is largely speculative; and
(3) That the debate on global warming has subsumed political and philosophical viewpoints which have complicated and prejudiced the scientific investigation of global warming phenomena; and

BE IT FURTHER RESOLVED, that the Legislature urges that all instruction on the theory of global warming be appropriate to the age and academic development of the student and to the prevailing classroom circumstances.

The senate of SD did pass a bill removing most of the crap above, but still left in the part about how global warming isn’t real because it is just a theory…like the theory of gravity, of the theory of relativity…you know just theories. One could only hope that they abandon all reason, and go out daily to test the “theory” of gravity by throwing themselves off high places.

In all honesty, if this is the best our leaders can muster, we have very little hope of making it as a species…I suggest you all start doing things on your own and/or get new leaders.

How Games Are Changing Everything

Written by The Naib

Imagine if this sort of thing was used for health, or carbon emissions, or whatever…this video is kind of blowing my mind…(note: not all in good ways, this also sort of made me dread the future)

Hairy Solar Cells: Cheap, Efficient, Potentially Revolutionary

Written by The Naib

Using arrays of long, thin silicon wires embedded in a polymer substrate, a team of scientists from the California Institute of Technology (Caltech) has created a new type of flexible solar cell that enhances the absorption of sunlight and efficiently converts its photons into electrons. The solar cell does all this using only a fraction of the expensive semiconductor materials required by conventional solar cells.

“These solar cells have, for the first time, surpassed the conventional light-trapping limit for absorbing materials,” says Harry Atwater, Howard Hughes Professor, professor of applied physics and materials science, and director of Caltech’s Resnick Institute, which focuses on sustainability research.


This is a photomicrograph of a silicon wire array embedded within a transparent, flexible polymer film.
[Credit: Caltech/Michael Kelzenberg]

The light-trapping limit of a material refers to how much sunlight it is able to absorb. The silicon-wire arrays absorb up to 96 percent of incident sunlight at a single wavelength and 85 percent of total collectible sunlight. “We’ve surpassed previous optical microstructures developed to trap light,” he says.

Atwater and his colleagues—including Nathan Lewis, the George L. Argyros Professor and professor of chemistry at Caltech, and graduate student Michael Kelzenberg—assessed the performance of these arrays in a paper appearing in the February 14 advance online edition of the journal Nature Materials.

Atwater notes that the solar cells’ enhanced absorption is “useful absorption.”

“Many materials can absorb light quite well but not generate electricity—like, for instance, black paint,” he explains. “What’s most important in a solar cell is whether that absorption leads to the creation of charge carriers.”

The silicon wire arrays created by Atwater and his colleagues are able to convert between 90 and 100 percent of the photons they absorb into electrons—in technical terms, the wires have a near-perfect internal quantum efficiency. “High absorption plus good conversion makes for a high-quality solar cell,” says Atwater. “It’s an important advance.”

The key to the success of these solar cells is their silicon wires, each of which, says Atwater, “is independently a high-efficiency, high-quality solar cell.” When brought together in an array, however, they’re even more effective, because they interact to increase the cell’s ability to absorb light.

“Light comes into each wire, and a portion is absorbed and another portion scatters. The collective scattering interactions between the wires make the array very absorbing,” he says.


This is a schematic diagram of the light-trapping elements used to optimize absorption within a polymer-embedded silicon wire array.
[Credit: Caltech/Michael Kelzenberg]

This effect occurs despite the sparseness of the wires in the array—they cover only between 2 and 10 percent of the cell’s surface area.

“When we first considered silicon wire-array solar cells, we assumed that sunlight would be wasted on the space between wires,” explains Kelzenberg. “So our initial plan was to grow the wires as close together as possible. But when we started quantifying their absorption, we realized that more light could be absorbed than predicted by the wire-packing fraction alone. By developing light-trapping techniques for relatively sparse wire arrays, not only did we achieve suitable absorption, we also demonstrated effective optical concentration—an exciting prospect for further enhancing the efficiency of silicon-wire-array solar cells.”

Each wire measures between 30 and 100 microns in length and only 1 micron in diameter. “The entire thickness of the array is the length of the wire,” notes Atwater. “But in terms of area or volume, just 2 percent of it is silicon, and 98 percent is polymer.”

In other words, while these arrays have the thickness of a conventional crystalline solar cell, their volume is equivalent to that of a two-micron-thick film. Or to put it yet another way, there is a lot of empty space in in there.

Since the silicon material is an expensive component of a conventional solar cell, a cell that requires just one-fiftieth of the amount of this semiconductor will be much cheaper to produce.

The composite nature of these solar cells, Atwater adds, means that they are also flexible. “Having these be complete flexible sheets of material ends up being important,” he says, “because flexible thin films can be manufactured in a roll-to-roll process, an inherently lower-cost process than one that involves brittle wafers, like those used to make conventional solar cells.”

Atwater, Lewis, and their colleagues had earlier demonstrated that it was possible to create these innovative solar cells. “They were visually striking,” says Atwater. “But it wasn’t until now that we could show that they are both highly efficient at carrier collection and highly absorbing.”

The next steps, Atwater says, are to increase the operating voltage and the overall size of the solar cell. “The structures we’ve made are square centimeters in size,” he explains. “We’re now scaling up to make cells that will be hundreds of square centimeters—the size of a normal cell.”

Atwater says that the team is already “on its way” to showing that large-area cells work just as well as these smaller versions.

In addition to Atwater, Lewis, and Kelzenberg, the all-Caltech coauthors on the Nature Materials paper, “Enhanced absorption and carrier collection in Si wire arrays for photovoltaic applications,” are postdoctoral scholars Shannon Boettcher and Joshua Spurgeon; undergraduate student Jan Petykiewicz; and graduate students Daniel Turner-Evans, Morgan Putnam, Emily Warren, and Ryan Briggs.

James Hansen Dropping Mad Knowledge On Foot Draggers

Written by The Naib

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