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Those fitted with magnetometers like the ones that provide your smartphone compass will transmit data about the Earth magnetic field.
Replacing today's gas-guzzling engines with electric motors means cars will no longer produce harmful emissions.
"But it only takes a handful to impact your local, neighbourhood transformer.##If you would like to comment on this article
Using ultraviolet and infrared rays as well as magnetic field sensors, the founder of Matsumura Engineering Co.,is targeting the fake U s. bills that are popping up in countries from South america to Asia and the Middle east.
the ELR electric motor acts as a generator while braking, automatically recovering energy that delivered to the batteries as electricity.
or simplify the mechanical gearbox normally associated with electric motors through so-called magnetic gears, an innovation that might be developed further in the project
Permanent magnet machines have a paramount importance in many other fields. Just to mention one, they are at the core of the electric generators used in all wind generators.
The project coordinated by The Chancellor, Masters and Scholars of the University of Cambridge, UK has 7 participants from 4 countries i
and a robotic platform that can operate inside the powerful magnetic field created by an MRI SCANNER.
The magnetic fields in magnetic resonance imaging (MRI) often disrupt either the function or safety of implanted electrical devices.
Like a series of small conveyer belts, localized rotating magnetic fields move the beads and cells along specific directions etched into a track,
In standard hospital instruments the magnetization of the atomic nuclei in the human body is measured inductively using an electromagnetic coil.
The nitrogen-vacancy center is both fluorescent and magnetic making it suitable for extremely precise magnetic field measurements.
The design builds on existing technology and creates a magnetic field within a closed space to hold plasma in place long enough for fusion to occur allowing the hot plasma to react and burn.
There are several ways to create a magnetic field which is crucial to keeping a fusion reactor going.
The new design is known as a spheromak meaning it generates the majority of magnetic fields by driving electrical currents into the plasma itself.
because they rely on superconducting coils that circle around the outside of the device to provide a similar magnetic field.
The materialâ could be the basis for unique electric generators that are lightweight bendable stretchable #and ultimately wearable. his material#just a single layer of atoms#could be made as a wearable device perhaps integrated into clothing to convert energy from your body movement to electricity
Magnetic field lines extend from the solar surface all the way into the corona. Moving and twisting bundles of field lines form magnetic flux tubes.
he system is turbulentthe magnetic field lines in the corona do not move in a random pattern
and magnetic fields. ntil now the complicated vibrations and rotations of molecules proved too difficult for such trapping.
and do it a lot of times. he slowed molecules enter a specially shaped magnetic field where opposing laser beams pass through the center of the field along three perpendicular axes.
which requires huge amounts of energy to maintain a magnetic field with electromagnets, the new method for enriching stable isotopes, called MAGIS (magnetically activated and guided isotope separation), needs little energy due to its use of low-powered lasers and permanent magnets.
The team previously reported the first observation of superfluorescence in a solid-state system by strongly exciting semiconductor quantum wells in high magnetic fields.
Previous experiments showed the ability to create superfluorescent bursts from a stack of quantum wells excited by a laser in extreme cold and under the influence of a strong magnetic field both
but mysteries remained especially in results obtained at low or zero magnetic fields. Kono says the team didn t understand at the time why the wavelength of the burst changed over its 100-picosecond span.
but also managed to record it without having to travel to the National High Magnetic field Laboratory at Florida State.
The quantum well as before consisted of stacked blocks of an indium gallium arsenide compound separated by barriers of gallium arsenide. t s a unique solid-state environment where many-body effects completely dominate the dynamics of the systemkono says. hen a strong magnetic field is applied electrons
and holes are fully quantizedâ##that is constrained in their range of motionâ##just like electrons in atomshe says. o the essential physics in the presence of a high magnetic field is quite similar to that in atomic gases.
and eventually eliminate the magnetic field we re entering a regime atomic physics cannot access where continua of electronic states
but it required high magnetic fields so there was no practical application. But now the present work demonstrates that we don t need a magnet. he team included co-lead authors Timothy Noe a Rice postdoctoral researcher and Ji-Hee Kim a former Rice postdoctoral researcher and now a research
Superconductivity is a quantum phenomenon that occurs as certain materials are cooled to near absolute zero thereby eliminating all electrical resistance and magnetic fields.
The findings published in the Proceedings of the National Academy of Sciences help scientists to interpret the dynamics of the core of the Earth the source of our planet s magnetic field.
and Environment at the University of Leeds. he magnetic field pushes eastwards on the inner core causing it to spin faster than the Earth
The fact that the Earth s internal magnetic field changes slowly over a timescale of decades means that the electromagnetic force responsible for pushing the inner and outer cores will itself change over time.
what the researchers have dubbed chemically otorized microscopic matchsticks. efore now most research seeking to influence the direction of motion of microscopic components have had to use outside influences such as a magnetic field
which governs motor control but instead the significant changes occurred in the SMA on the opposite side of the trained hand.
##Dynamo accounts for Sun s weather cycle University of Chicago University of Leeds rightoriginal Studyposted by Richard Mellor-Leeds on May 23 2013u.
what drives the generation of astrophysical magnetic fields like the Sun s. Scientists have known since the 18th century that the Sun regularly oscillates between periods of high and low solar activity in an 11-year cycle
It has become increasingly important to be able to understand the Sun#s magnetic activity as it is the changes in its magnetic field that are responsible for#space weather#phenomena including solar flares and coronal mass ejections.
The research published in Nature explains how the cyclical nature of these large-scale magnetic fields emerges providing a solution to the mathematical equations governing fluids and electromagnetism for a large astrophysical body.
The mechanism known as a dynamo builds on a solution to a reduced set of equations first proposed in the 1950s
#Previously dynamos for large highly conducting bodies such as the Sun would be overwhelmed by small-scale fluctuations in the magnetic field.
In addition this mechanism could be used to describe other large spinning astronomical bodies with large-scale magnetic fields such as galaxies.
The dynamo was developed through simulations using the high-performance computing facilities located at the University of Leeds.#The fact that it took 50 years
and huge supercomputers shows how complicated the dynamo process really is#says Professor Fausto Cattaneo of the University of Chicago#s department of astronomy and astrophysics.
At the start of the 20th century it was recognized then that these sunspots were the result of the Sun#s magnetic field.
and any passengers into rotational thrust to charge a battery and power the vehicle in conjunction with an electric motor.
It can be powered by one, two, three or four people, the battery-powered electric motor, or any combination of human and electric power.
Magnetoencephalography (MEG) is a noninvasive procedure that measures the magnetic fields generated by the brain. This helps neuroscientists understand perceptual and cognitive processes
which is 50 million times weaker than the Earth's magnetic field.""By making an inexpensive system you could have one in every hospital to test for traumatic brain injuries
In addition, a series elastic actuator consisting of an electric motor with a spring in series with its output shaft that allows the actuator to gauge
and is reportedly five thousand times more conductive making it ideal for carrying higher currents such as those required by small electric motors and other actuators.
#Volocopter VC200 18-rotor electric helicopter takes flight Volocopter VC200 Greener transportation options have become a priority in the modern world.
It has 18 rotors, along with 18 zero emission motors powered by six battery packs. Its frame is created from carbon fiber to keep the aircraft lightweight and It seats two people.
##which have four helicopter rotors. The machines can catch a ball and perform other autonomous feats of balance and coordination.
which produces a magnetic field. When a car with its own coil is placed above the transmitter,
the magnetic field induces a flow of power that charges the batteries. Stationary inductive chargers for electric vehicles typically use sensors to ensure that the receiver coils on the vehicle are aligned above wireless charging pads correctly.
electronics in the receiver trigger a strong magnetic field and an accompanying flow of power, says Lukic.
Precisely controlling when the roadway coils produce a magnetic field is important for safety reasons; if the field misses the car s receiving coils,
or contain the magnetic field produced by the transmitter to always be right below the receiver.
and magnetic field, says Lukic. The coupling between transmitter and receiver could be done with power electronics
#Electric power without transmission lines Hundreds of companies are investing in electricity transferred through magnetic fields. Nikola Tesla, the inventor and rival to Thomas Edison, in the early 1900##s built the Wardenclyffe Tower, a 187-foot-high structure on Long island,
to take the wires out of the power equation by transmitting electricity through magnetic fields. When in the atmosphere, electricity exists as a magnetic field.
The trick is to capture it safely to recharge devices. Today s electric toothbrushes charge wirelessly##as power is transmitted through a magnetic field from the charger to the brush.
You can already buy wireless recharging pads: Place your cellphone on a pad that s plugged into the wall,
The FCC has set limits for magnetic fields, and Witricity claims its devices fall well below that threshold.
What wee doing is putting a magnetic field in the air. It works like this: Witricity build a ource Resonatora coil of electrical wire that generates a magnetic field
when power is attached. If another coil is brought close, an electrical charge can be generated in it.
No wires required. hen you bring a device into that magnetic field, it induces a current in the device,
Hall assures that the magnetic fields used to transfer energy are erfectly safein fact, they are the same kind of fields used in Wi-fi routers.
Video)##The aircraft, called quadcopters because they have four rotors, navigate using signals from Global Positioning System (GPS) receivers,
the devices that we work with nowadays do not allow for building up skill on a motor control level.
#Real-life Transformer: Robotic bug springs to life The latest advancement in robotics may not look like much just a few small batteries attached to a flat sheet of paper
This real-world Transformer developed by computer and electrical engineers at the Massachusetts institute of technology (MIT) and Harvard university, could change the field of robotics.
See video of the real-life transformer in action Origami robots The new robots were inspired in part by origami, the Japanese art of paper folding.
The twisted fiber creates an artificial muscle that can drive a heavy rotor at a speed of more than 10000 revolutions per minute.
MRI machines use a magnetic field to get hydrogen atoms in the body spinning in a particular way,
For decades, researchers have suspected that powerful magnetic fields are heating the corona. The Sun's atmosphere is just jam-packed full of magnetic field,
says Cirtain. As the lines of those fields cross and twirl, the theory went, they push and pull the charged gas in the corona, giving it the energy that heats it up.
The problem is that nobody has been able to see the magnetic fields in close up until now. Cirtain and his team have developed the High-resolution Coronal Imager (Hi-C
Using lasers and magnetic fields they kept the individual atoms in a lattice arrangement. At positive temperatures, the atoms repel,
The team then quickly adjusted the magnetic fields, causing the atoms to attract rather than repel each other."
electrically charged particles, corralled into separate doughnut-shaped rings by Earth s magnetic field. The outer ring orbits at a distance of some 10,000-60,000 kilometres above Earth,
repulsive magnetic field that forces the board up into the air and allows it to levitate.
where guided by magnetic fields it could be used to scout around and deliver medicines to specific locations.
which its moving by a set of electromagnetic coils underneath. T hose coils generate directional electromagnetic fields that cycle on
Secondly, the particles can be triggered by an outside magnetic field to produce an electric field when adjacent to individual neurons.
should be able to communicate directly with the brain electric field. hen MENS are exposed to even an extremely low frequency magnetic field,
the nanoparticles could generate measurable magnetic fields in response to the brain electrical fields. Toggle the system back
The magnetic field is shaped to pull the gadolinium downward so metal particles push the cells upward,
Conventional MRIS found in hospitals work by inducing a magnetic field gradient across your entire body.
Additional radio signals cause the protons in your body's liquids to resonate with the magnetic field
Instead of creating a magnetic field across the entire body the device sends superfast radio pulses into a small area of the body like a wrist.
when the movement of the wind's particles is perpendicular to the sun's magnetic field they resemble a fluid with sections that are smooth interrupted by bursts of violence.
which can cause plasma to escape the magnetic field containing it in the reactor. They may also be able to use turbulence to disrupt high energy plasma blobs that can rip holes in the reactor.
Magnetic field lines threading through those shells should get compressed and aligned causing some of the material to line up as well.
And Jupiter's strong magnetic field means that intense radiation surrounds the moon which makes it difficult for spacecraft to operate.
But sometimes the sun's magnetic field lines can directly link up with Earth's in a process called magnetic reconnection which opens up cracks in the magnetosphere.
and the resulting plasma becomes trapped by magnetic fields in a doughnut-shaped ring around the planet.
This would make it harder for magnetic field lines to meet up and spark further reconnection. But while ground-based measurements can see a plume forming their resolution isn't good enough to tell for sure
For the first time we were able to monitor the entire cycle of this plasma stretching from the atmosphere to the boundary between Earth's magnetic field
and carefully shaped magnetic field that stops xenon ions from hitting the engine walls and going to waste.
Earth is protected from the solar wind by a relatively strong global magnetic field which repels charged particles from the sun explains Nick Schneider of the Laboratory for Atmospheric
And while Mars is farther away it has no global magnetic field. It is thought the solar wind thinned the Red planet's atmosphere over time making it cold and dry.
They are deflected not by magnetic fields as they travel so neutral atoms faithfully record the point of collision.
The magnetic field of the heliosphere protects us from the bulk of these galactic high-energy particles. But some manage to impinge on our solar system
The planet also only briefly had a magnetic field to protect its surface from cosmic radiation
at developing advanced drivetrain controls and rotor designs. ut out of that study we spotted tower transport as one of the biggest bottlenecks holding back the industry,
In the presence of a magnetic field the paired particles begin to tumble across a surface with first one particle
This animation shows micro walkers tumbling across a surface under the influence of a rotating magnetic field until they find areas where friction is represented highest by the orange area.
At the same time the nanoparticles could be manipulated precisely by applying a magnetic field to pull them along. And finally the particles could have a coating of a bioreactive substance that could seek out
Moreover Bawendi says We wanted to be able to manipulate these structures inside the cells with magnetic fields
and electric motors that weighs about as much as its feline counterpart. The team recently took the robot for a test run on MIT s Killian Court where it bounded across the grass at a steady clip.
Kim says what makes the robot so dynamic is designed a custom high-torque-density electric motor designed by Jeffrey Lang the Vitesse Professor of Electrical engineering at MIT.
The combination of such special electric motors and custom-designed bio-inspired legs allow force control on the ground without relying on delicate force sensors on the feet.#
When exposed to a powerful magnetic field hydrogen atoms align their spins in the same direction. When a second smaller field perturbs the atoms they should all change their spins in synchrony
Each motor controls two of the robot s legs; the motors are synchronized by the microprocessor. Each leg in turn has eight mechanical linkages
#New material structures bend like microscopic hair MIT engineers have fabricated a new elastic material coated with microscopic hairlike structures that tilt in response to a magnetic field.
Zhu chose to work with materials that move in response to a magnetic field. Others have designed such magnetically actuated materials by infusing polymers with magnetic particles.
Melanie Gonick/MIT Instead she and Zhu chose to manufacture an array of microscopic pillars that uniformly tilt in response to a magnetic field.
The researchers exposed the material to an external magnetic field placing it between two large magnets
which tilted toward the angle of the magnetic field. We can apply the field in any direction
Under a magnetic field the liquid only flowed in the direction in which the pillars tilted
In principle she says more complex magnetic fields could be designed to create intricate tilting patterns throughout an array.
Or depending on how you design the magnetic field you could get the pillars to close in like a flower.
the rotor of a helicopter may actually move detectably between the reading of one row and the reading of the next.
Varanasi s team decided to use external fields such as magnetic fields to make surfaces active exerting precise control over the behavior of particles
and pulled by applying a magnetic field to the surface. When droplets of water or tiny particles are placed on the surface a thin coating of the fluid covers them forming a magnetic cloak.
or fluids these require the material being moved to be magnetic and very strong magnetic fields to move them around.
First in 2007 the team wirelessly lit a 60-watt light bulb from eight feet away using two large copper coils with similarly tuned resonant frequencies that transferred energy from one to the other over the magnetic field.
which uses an electromagnetic field to transfer energy between two coils is used in transformers and wireless toothbrushes.
The transmitter emanated a magnetic field oscillating at megahertz frequencies which the receiver matched ensuring a strong coupling between the units
For their first power-producing prototype they bought a small reliable wind turbine rotor and cut off some metal in the back that was dead weight
(which Rein co-founded) in Somerville Mass. where its first rotor is displayed proudly near the entrance along with enlarged photos of the first trial run.
Long-term MRIMRI uses magnetic fields and radio waves that interact with protons in the body to produce detailed images of the body s interior.
which in turn releases the energy to the electric motor during acceleration. Custom software reads the driver s braking habits
An XL Hybrids electric motor adds torque to an existing powertrain meaning a customer can reduce the size of the engine from say a 6-liter to a 4. 8-liter
Another imaging technique, known as magnetoencephalography (MEG), uses an array of hundreds of sensors encircling the head to measure magnetic fields produced by neuronal activity in the brain.
When a current passes through an inductor, it generates a magnetic field which in turn resists any change in the current.
and the inverters that convert the battery power to drive the electric motors. The silicon transistors used today have constrained a power capability that limits how much power the car can handle.
In their experiments Shi and his team exposed the graphene to an external magnetic field. They found that graphene's Hall voltage-a voltage in the perpendicular direction to the current flow-depended linearly on the magnetization of yttrium iron garnet (a phenomenon known as the anomalous Hall effect seen in magnetic materials like iron and cobalt.
when exposed to alternating magnetic fields causing cell death (magnetic hyperthermia). The UCD team led by Conway Fellows Professor Gil Lee in the School of Chemistry
creating the possibility of electric generators powered by air. One-atom thick material graphene first isolated and explored in 2004 by a team at The University of Manchester is renowned for its barrier properties
They hypothesise that such harvesting can be combined together with fuel cells to create a mobile electric generator that is fuelled simply by hydrogen present in air.
and close and ultimately how the device moves by applying an external magnetic field. However the researchers'discovery that micro-devices can swim through some liquids with symmetrical movements does not just apply to magnetically-driven micro-robots.
When they then applied a rotating magnetic field the nickel-containing nano-screw also started to rotate causing the propeller to move forward through a liquid.
#New nanomaterial introduced into electrical machines Lappeenranta University of Technology in Finland has constructed the world's first prototype electrical motor using carbon nanotube yarn in the motor windings.
The presently most electrically conductive carbon nanotube yarn replaces usual copper wires in the windings. The motor prototype is built by the LUT Electrical engineering group as a start towards lightweight efficient electric drives.
In the near future carbon nanotube fibers have potential to significantly enhance the performance and energy efficiency of electrical machines.
Researchers are constantly searching for opportunities to upgrade the performance of electrical machines; to this end one of the objectives is to find higher-conductivity wires for the windings.
The best carbon nanotubes (CNTS) have demonstrated conductivities far beyond those of the best metals. Thus future windings made of CNTS may have a double conductivity compared with the present-day copper windings.
In order to make CNTS easy to manipulate they are spun to form multifiber yarn. If we keep the electrical machine design parameters unchanged and only replace copper with future carbon nanotube wires it is possible to reduce the Joule losses in the windings to half of the present-day machine losses.
Carbon nanotube wires are significantly lighter than copper and also environmentally friendlier. Therefore replacing copper with nanotube wires should significantly reduce the CO2 EMISSIONS related to the manufacturing
and operating of electrical machines. Furthermore the machine dimensions and masses could be reduced. The motors could also be operated in significantly higher temperatures than the present ones says Professor Juha Pyrh nen who has led the design of the prototype at LUT.
No definite upper limit for the conductivity Traditionally the windings in electrical machines are made of copper which has the second best conductivity of metals at room temperature.
Despite the high conductivity of copper a large proportion of the electrical machine losses occur in the copper windings.
According to Pyrhnen the electrical machines are so ubiquitous in everyday life that we often forget about their presence.
In a single-family house alone there can be tens of electrical machines in various household appliances such as refrigerators washing machines hair dryers and ventilators.
All these use copper in the windings. Consequently finding a more efficient material to replace the copper conductors would lead to major changes in the industry tells Professor Pyrh nen.
There is a significant improvement potential in the electrical machines but we are now facing the limits of material physics set by traditional winding materials.
Superconductivity appears not to develop to such a level that it could in general be applied to electrical machines.
We expect that in the future the conductivity of carbon nanotube yarns could be even three times the practical conductivity of copper in electrical machines.
Their magnetic fields can be thought of as being coupled into one, and the"north-south"polarity of the magnet that is free to flip will be determined by the orientation of the majority of fixed magnets.
The electric and magnetic fields of the particle accelerator then organize the electrons into a beam. The tested nanotube cathode requires no laser:
#Magnetic field opens and closes nanovesicle Chemists and physicists of Radboud University managed to open and close nanovesicles using a magnet.
Because the strength of the magnetic field is linked precisely to the size of the vesicles the deformation can be controlled more easily.
without the magnetic field the vesicles close and they open when the field is turned on. After switching the field off they return to a closed state.
if we could steer these rockets with magnetic fields but to our surprise the vesicles opened during those experiments.
We also hope to find materials for which the same effect occurs in a lower magnetic field-that of an MRI.
The particles are collected in a magnetic field undeposited contaminants are washed away and the purified antibodies recovered by removing the polyethylene glycol.
because graphene droplets change their structure in response to the presence of an external magnetic field,
The scientists were able to control the motion of the propellers using a relatively weak rotating magnetic field.
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