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SEC college football power rankings led by Alabama, Georgia, Florida

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Alabama crushed Texas A&M (again). Once relevant, this series sits firmly in the Crimson Tide’s corner.

Ole Miss landed the first win of the Lane Kiffin era by topping Kentucky in overtime. Already, you can see how the Rebels’ offense will cause trouble in the SEC.

And in the biggest game of the week, Georgia beat Auburn to solidify its place in the College Football Playoff race.

The second weekend of the SEC season was a revealing one. What’s clear: Alabama, Florida and Georgia are the teams to beat. After two games, here’s an updated look at the conference power rankings.

1. Alabama (Last week: No. 1)

The Crimson Tide don’t budge from atop the list after a 52-24 win against Texas A&M paced by quarterback Mac Jones, who had three touchdown passes of at least 60 yards. Aided by an explosive receiver corps, Jones has gone from a question mark heading into the preseason to a part of the Heisman Trophy race.

2. Georgia (No. 3)

Sluggish in a win against Arkansas to kick off the year, Georgia put together a more complete performance to beat Auburn 27-6 and climb into second place behind Alabama. The Bulldogs controlled the line of scrimmage and protected quarterback Stetson Bennett, who threw for 240 yards.

Georgia defensive back Mark Webb intercepts a pass in front of Auburn wide receiver Anthony Schwartz during the second half at Sanford Stadium. (Photo: Dale Zanine, USA TODAY Sports)

3. Florida (No. 2)

Florida’s rebuild on offense is complete. The Gators have a pair of Heisman Trophy contenders in quarterback Kyle Trask, who threw for another four touchdowns in a 38-24 win against South Carolina, and tight end Kyle Pitts, who now has six scoring grabs through two

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Atomic Motion Of Graphene Generates Limitless Power, Study Finds

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KEY POINTS

  • Study shows graphene moves in a back and forth manner similar to how electrons behave in a circuit
  • Physicists invent a circuit that can convert energy from graphene into an electrical current
  • The study result has became significant in today’s search for a clean energy source

The world may soon have a clean and limitless energy source powered by a circuit that harvests electricity from the atomic motion of graphene. The technology comes in the form of small chips that have the potential of replacing disposable energy sources and saving people from the lifetime purchase of small batteries. 

A team of physicists from the University of Arkansas presented their invention of a circuit that can capture the thermal motion of graphene and convert it into an electrical current. The study, published in the journal Physical Review E, explored a finding three years ago that first identified graphene as a strong candidate for harvesting energy.     

For the present study, the team found that graphene moves in a back and forth manner similar to how electrons behave in a circuit. The manner in which the graphene moves is more apparent at room temperature, the team said in the study. In fact, graphene’s thermal motion showed signs that it can induce an alternating current (AC) seen in electric circuits. 

graphene 2 Scientists have found a cheap and quick way to manufacture graphene. In this photo, senior technologist Dariusz Czolak
holds a piece of silicon carbide disk covered with a layer of graphene, obtained in the process of epitaxy, in the Institute of Electronic Materials Technology (ITME) laboratory in Warsaw on Oct 23, 2012.
Photo: Reuters/Kacper Pempel

“An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,” lead researcher Paul Thibado 

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Graphene-based circuit yields clean, limitless power

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Oct. 2 (UPI) — Scientists have developed a new graphene-based circuit capable of producing clean, limitless power. Researchers suggest the energy-harvesting circuit — described Friday in the journal Physical Review E — could be used to power small, low-voltage devices and sensors.

The circuit’s ability confirms the theory — developed by the study’s authors, a group of physicists at the University of Arkansas — that micron-sized sheets of freestanding graphene naturally move in a way conducive to energy harvesting.

The breakthrough also contradicts the assertion by Richard Feynman that so-called Brownian motion, the thermal motion of atoms, cannot perform work. But lab tests showed the Brownian motion of atoms in freestanding sheets of graphene can generate an alternating current.

Famously, physicist Léon Brillouin proved that a single diode, a one-way electrical gate, added to a circuit was not sufficient to turn Brownian motion into energy. The team of physicists at the University of Arkansas developed their novel circuit using two diodes.

Positioned in opposition, the two diodes allow current to flow in both directions, turning the alternating current into a pulsing direct current. The pulsing direct current, taking separate paths back-and-forth through the circuit, performs work on a load resistor.

“We also found that the on-off, switch-like behavior of the diodes actually amplifies the power delivered, rather than reducing it, as previously thought,” lead researcher Paul Thibado, professor of physics at Arkansas, said in a news release. “The rate of change in resistance provided by the diodes adds an extra factor to the power.”

According to the researchers, the thermal movement in the graphene and circuit is inherent in the material, not the result of temperature differences between the two components — no heat flows between the graphene and circuit.

“This means that the second law of thermodynamics is not

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MIT physicists inch closer to zero-emissions power source

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Sept. 29 (UPI) — For the last few years, scientists at MIT have been working on a fusion research experiment called SPARC and, according to a series of papers — published Tuesday in the Journal of Plasma Physics — the research is going quite smoothly.

The research effort, a collaboration between MIT and startup company Commonwealth Fusion Systems, is intended to pave the way for an emissions-free power plant — a fusion reactor.

According to the latest updates, scientists have yet to encounter any unexpected hurdles. What’s more, researchers characterized the remaining challenges as manageable.

Over the last 2 1/2 years, researchers on the project have focused on working out the physical principles underlying their planned fusion reactor. So far, the work has confirmed the validity of the plasma physics behind their SPARC plans.

“These studies put SPARC on a firm scientific basis,” Martin Greenwald, researcher at the MIT Plasma Science and Fusion Center, said in a news release.

“When we build and operate the machine as described in these papers, we fully expect to meet our target for fusion gain and produce a wealth of new and important information on burning plasmas,” said Greenwald, who served as guest editor for the special edition of Journal of Plasma Physics.

Engineers expect their SPARC reactor, or tokamak, to be much more powerful than previous experimental reactors. The reactor will take advantage of advances in superconducting magnets, which will produce a more powerful magnetic field, capable of confining SPARC’s hot plasma.

In the new papers, scientists outlined the calculations and simulation tools that were used to confirm SPARC’s underlying physics.

The primary goal for the SPARC experiment is to achieve a Q factor — a measure of fusion plasma efficiency — of at least 2, an ability to generate double the energy

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