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Bacterial wires explain enigmatic electric currents in the seabed: Each one of these 'cable bacteria' contains a bundle of insulated wires that conduct an electric current from one end to the other. Cable bacteria explain electric currents in the seabed Electricity and seawater are usually a bad mix.

WOW!!!! don't want to even imagine what we do to these with the trailing fishing boats that sweep through sea beds with large masses .... "Our experiments showed that the electric connections in the seabed must be solid structures built by bacteria," says PhD student Christian Pfeffer, Aarhus University. He could interrupt the electric currents by pulling a thin wire horizontally through the seafloor. Just as when an excavator cuts our electric cables. In microscopes, scientists found a hitherto unknown type of long, multi-cellular bacteria that was always present when scientists measured the electric currents. "The incredible idea that these bacteria should be electric cables really fell into place when, inside the bacteria, we saw wire-like strings enclosed by a membrane," says Nils Risgaard-Petersen, Aarhus University. Kilometers of living cables The bacterium is one hundred times thinner than a hair and the whole bacterium functions as an electric cable with a number of insulated wires within it. Quite similar to the electric cables we know from our daily lives. "Such unique insulated biological wires seem simple but with incredible complexity at nanoscale," says PhD student Jie Song, Aarhus University, who used nanotools to map the electrical properties of the cable bacteria. In an undisturbed seabed more than tens of thousands kilometers cable bacteria live under a single square meter seabed. The ability to conduct an electric current gives cable bacteria such large benefits that it conquers much of the energy from decomposition processes in the seabed. Unlike all other known forms of life, cable bacteria maintain an efficient combustion down in the oxygen-free part of the seabed. It only requires that one end of the individual reaches the oxygen which the seawater provides to the top millimeters of the seabed. The combustion is a transfer of the electrons of the food to oxygen which the bacterial inner wires manage over centimeter-long distances. However, s

Unlike any other living thing on Earth, electric bacteria use energy in its purest form - naked electricity in the shape of electrons harvested from rocks and metals. We already knew about two types, Shewanella and Geobacter. Now, biologists are showing that they can entice many more out of rocks and marine mud by tempting them with a bit of electrical juice. Experiments growing bacteria on battery electrodes demonstrate that these novel, mind-boggling forms of life are essentially eating and excreting electricity.

Artificial cells could be built that not only replicate the electrical behavior of electric eel cells but in fact improve on them. Artificial versions of the eel's electricity generating cells could be developed as a power source for medical implants and

A good electrical conductor is normally a good heat conductor. Vanadium dioxide however seems to not be so, by being a good electrical conductor and a poor thermal conductor. Paper at http://science.sciencemag.org/content/355/6323/371

A personal interest of mine that I want to explore a bit more in the future. I just bought a ZigBee electricity monitor and I am wondering whether from the signal of the mains one could detect (reliably) the oven turning on, lights, etc. Probably requires Neural Network training. The idea would be to make a simple device which basically saves you money by telling you how much electricity you are wasting. Then again, its probably already done by Google...

Randomly I found this: http://spectrum.ieee.org/view-from-the-valley/consumer-electronics/gadgets/curb-startup-home-electricity-tracking Isn't it a similar kind of stuff Thijs?

haha, yep, that's it... but we can do better than that right! :)

A new experiment proved the existence of a new effect in nanomaterials: flexo-electric effect. The material has built-in mechanical tension that changes shape when you apply electrical voltage, or that generates electricity if you change its shape and was theorized some decades ago. Now, SrTiO3 allowed to observe this new effect, being comparable with piezoelectric effect.

My old twente university group! :)

Isn't muscle wire quite old technology though?

The "Effizienzhaus-Plus mit Elektromobilität" (Google translation: House-Plus efficiency with electric mobility) project is a German government-backed initiative to build an energy-efficient house that generates more electricity than it consumes. It will see a family of four living in the house located in Berlin for fifteen months, starting in March 2012. Audi, BMW, Daimler, Opel and VW will each get a chance to put their respective electric vehicles to the test with each providing EVs to the house for periods of three months each.

The principle behind that is Nantenna.

this is fantastic!!!! waiting of somebody to make this happen since years The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of their extremely small and fast tunnel diodes, are capable of converting solar radiation in the infrared region through the extremely fast and short wavelengths of visible light - something that has never been accomplished before. Silicon solar panels, by comparison, have a single band gap which, loosely speaking, allows the panel to convert electromagnetic radiation efficiently at only one small portion of the solar spectrum. The rectenna devices don't rely on a band gap and may be tuned to harvest light over the whole solar spectrum, creating maximum efficiency. Through atomic layer deposition, Willis has shown he is able to precisely coat the tip of the rectenna with layers of individual copper atoms until a gap of about 1.5 nanometers is achieved. The process is self-limiting and stops at 1.5 nanometer separation The size of the gap is critical because it creates an ultra-fast tunnel junction between the rectenna's two electrodes, allowing a maximum transfer of electricity. The nanosized gap gives energized electrons on the rectenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the rectenna makes it hard for the electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current. Impressively, the rectennas, because of th

thin flexible sheets that can transmit electrical energy to nearby devices without the need for direct electrical contact.

A new discovery from a chemist at the University of Texas at Austin may allow photovoltaic solar cells to double their efficiency, thus providing loads more electrical power from regular sunlight.

We discussed this today during coffee. The inventor claims that he claims that a pressure differential can push hydrogen through a proton conductive membrane (thereby stripping off the electrons) which flow through an electric circuit and provide electric power. The type of membrane is fairly similar to that found in a hydrogen fuel cell. If the pressure differential is cause by selective heating this is in essence a heat engine that directly produces electricity. The inventor claims that this could be a high efficiency alternative to thermoelectric devices and could even outperform PV and Sterling engines with an efficiency close to that of fuel cells (e.g., ~60% @ dT=600K). I could not find any scientific publications as the inventor is not affiliated to any University - he has however an impressive number of patents from a very wide field (e.g., the "Super Soaker" squirt gun) and has worked on several NASA and US military projects. His current research seams to be funded by the latter as well. Here are some more links that I found: http://www.theatlantic.com/magazine/archive/2010/11/shooting-for-the-sun/308268/ http://www.johnsonems.com/?q=node/13 http://scholar.google.nl/scholar?q=%22lonnie+g+johnson%22+&btnG=&hl=nl&as_sdt=0%2C5

The drone derived craze takes on new life. Still not too bad for electric.

Do you know this one ? (no time to go through the bookmarks...)

They just got 1.7 million euros from the EU "to build the laboratory prototypes of the key components of the electric sail": http://en.ilmatieteenlaitos.fi/press-release/121643

very interesting info indeed!!

"The first thing everyone did after seeing the energy graph on the family PC was to turn off the lights". Kind-of we are becoming slaves of the technology. Do we really need a sensor to tell us to turn-off the light when we are leaving the room!?

electric grid modelling .... Nikolaos could you have a look at this?

electrically charged spider web ...

With electrical signals, cells can organize themselves into complex societies and negotiate with other colonies.

The article came out some time ago of course and was posted here, though the story here is still well written. If you are lazy to read the rel long article, here the summary explanation: The team found that a good half of the force came from heat from the RTGs, which bounced off the back of the spacecraft antenna. The other half came from electrical heat from circuitry in the heart of the spacecraft. Most of that heat was radiated through louvers at the back of the probes, which weren't as well insulated as the rest of their bodies, further contributing to the deceleration.

This is the first time that significant pair production has been demonstrated in a structure that can be electrically self-pumped and which can form the basis for passive optical circuitry, bringing us markedly closer to complete integration of quantum optical technologies.