Metallic conductivity and hydrophilicity of MXenes have established
them as electrodes in rechargeable batteries and supercapacitors, as well as other applications, including photothermal cancer therapy, electromagnetic shielding, water purification and gas sensing.
The new approach uses yarns, made from nanowires of the element niobium,
as the electrodes in tiny supercapacitors (which are essentially pairs of electrically conducting fibers with an insulator between).
The highly conductive foam was tested
as an electrode in lithium ion capacitors and found to be mechanically and chemically stable.
If the researchers can use multiple diamond tips in different shapes and further control the process, «one can envision forming a predesigned ribbon network ready to serve
as electrodes in a specific circuitry of a future device,» he says.
In the journal Review of Scientific Instruments [abstract], from AIP Publishing, the researchers detail the fabrication and optimization of the device, which is based on a phosphor screen and single - walled carbon nanotubes
as electrodes in a diode structure.
Not exact matches
Traumatic birthing experiences, like the use of drugs to induce labor and numb pain, internal
electrode probes screwed onto baby's scalp, forceps, C - section, immediate cord clamping, suctioning, rough handling, bright lights, separation from mom and being left alone
in a nursery incubator etc., can be hard - wired into a deep memory base that you,
as a now functioning adult, can't even remember, let alone access!
In devices known as capacitors, energy is physically stored in an electric field between metal electrode
In devices known
as capacitors, energy is physically stored
in an electric field between metal electrode
in an electric field between metal
electrodes.
Their experiments show that
electrodes are wetted twice
as fast
in a vacuum
as under normal pressure.
Then, Feng recognized a novel opportunity to directly measure whether tDCS generates EFs
in deep brain areas among patients with movement disorders such
as Parkinson's disease, who are often treated by implanting DBS
electrodes.
In other words, 4 mA current produced about twice
as much voltage change across
electrodes as 2 mA current and the bi-temporal montage provided higher voltage differences than the occipitofrontal montage.
As I had seen
in the video
in Schalk's office, each patient had the top of his skull removed and
electrodes affixed to the surface of the cortex.
The results of this work could lead to the ability to design materials that have extensive surface areas that can be used
in batteries
as high durability silicon
electrodes.
The prosthesis proposed by John Pezaris, an assistant
in neuroscience at Massachusetts General Hospital (MGH)
in Boston — at least
as it's envisioned at this early stage — would be worn like a pair of eyeglasses, with digital cameras over a person's eyes that connect to an array of
electrodes implanted
in the brain.
Having the
electrode in the form of tiny suspended particles instead of consolidated slabs greatly reduces the path length for charged particles
as they move through the material — a property known
as «tortuosity.»
In fact, there have been many efforts to improve lithium - ion battery or supercapacitor performance using alternative
electrode materials such
as carbon nanotubes and other manganese oxides.
For the past eight years, he and his colleagues have been studying epilepsy patients who have had
electrodes implanted
in a region of their brains called the medial temporal lobe,
as part of a study to identify the source of their seizures.
Used
as a counter
electrode in a dye - sensitized solar cell, the material enabled the cell to convert power with up to 6.8 percent efficiency and more than doubled the performance of an identical cell that instead used an expensive platinum wire counter
electrode.
As a result,
electrodes in the ICX began to pick up neural responses to flashes of light, he reports
in the 30 August issue of Science.
As batteries are used and charged, the electrochemical reaction results
in the movement of ions between the two
electrodes of a battery, which is the essence of an electrical current.
Metal nitrides such
as titanium nitride, which offer both high conductivity and capacitance, are a promising alternative, but they tend to oxidize
in watery environments that limits their lifetime
as an
electrode.
«Using a new layer - by - layer fabrication process, we created a microfluidic environment
in which TEER - measuring
electrodes are integral components of the chip architecture and are positioned
as close
as possible to the tissues grown
in one or both of two parallel running channels,» said Olivier Henry, Ph.D., a Wyss Institute Staff Engineer who was the driving force behind the new Organ Chip designs.
In the case of diagnostic methods such
as electrocardiogram (ECG) and electromyography (EMG), gel
electrodes are the preferred method of transmitting electric impulses from the heart or muscle.
Using sunlight to create fuels (such
as hydrogen on the other
electrode in this solar cell) with inexpensively prepared
electrodes may provide a solution to the intermittency drawback of solar energy.
Through a chemical process known
as reduction / oxidation, one
electrode steals electrons from glucose, the natural sugar
in the blood, and becomes an anode, which releases electrons.
The team asked the patients to categorize a variety of images
as fast
as possible while their
electrodes recorded the firing of nearly 1,500 single brain cells across the group
in real time.
Schroeder and colleagues have caught this action
in monkeys» brains, and more recently,
in people implanted with
electrodes as part of epilepsy treatment.
Miller and colleagues saw this push - and - pull action
in the brains of monkeys with implanted
electrodes as the animals completed a tricky memory task, one that required the monkeys to hold several pieces of information
in their minds at the same time.
In a new study by Flesher et al., microelectrode arrays were implanted into the primary somatosensory cortex of a person with spinal cord injury and, by delivering current through the
electrodes, generated sensations of touch that were perceived
as coming from his own paralyzed hand.
Unlike the
electrodes used
in lithium - ion batteries, these organic compounds don't rely on intercalation — the process of continuously integrating ions into their molecular matrix, which slows down
as the temperature drops.
«Until now, the only way to achieve this was a risky surgical procedure known
as deep brain stimulation,
in which
electrodes are implanted directly inside the thalamus,» he said.
In a real battery, thousands of these particles form an electrode, and positively charged lithium ions embed in the electrode as the battery charge
In a real battery, thousands of these particles form an
electrode, and positively charged lithium ions embed
in the electrode as the battery charge
in the
electrode as the battery charges.
As the name implies, the technique involves electrical currents flowing through
electrodes in random pulses, activating neurons
in multiple brain areas.
One strategy has been to try to transform the
electrodes from flat sheets into a forest - like array of carbon pillars, which are then wired together
in long alternating rows to serve
as negative and positive
electrodes.
A result is that a property known
as the capacitance decreases, which
in turn raises the voltage between the two
electrodes.
Laid down
in thin films, randomly oriented carbon nanotubes form conductive networks that can serve
as electrodes; patterned and layered films can function
as sensors or transistors.
In 1990, Garnier's team unveiled a transistor made mostly from plastics; but this still needed some metallic components, such
as gold and silver for the
electrodes (Technology, 15 December 1990).
«Being able to tell if there is a tendency for a reaction to take place
in a specific part of the
electrode, and better yet, the location of reactions within individual nanoparticles
in the
electrode, would be extremely useful because then you could understand how those localized reactions correlate with the behavior of the battery, such
as its charging time or the number of recharge cycles it can undergo efficiently,» Cabana said.
How one woman learned to use the
electrodes implanted
in her brain
as an extension of her nervous system.
In particular, they have to increase the number of charge / discharge cycles significantly, which could be achieved by improving battery and
electrode designs
as well
as by using coatings other than reduced graphite oxide.
These alternative
electrodes could be capable of storing nearly three times
as much energy
as graphite, the material of choice
in current lithium - ion batteries.
As a result, an electrode particle swells as a whole, i.e. it increases in volume only to shrink again once the charges leave the particl
As a result, an
electrode particle swells
as a whole, i.e. it increases in volume only to shrink again once the charges leave the particl
as a whole, i.e. it increases
in volume only to shrink again once the charges leave the particle.
One group turned to an electrochemical approach, which can be adapted for
in - the - field use, but their technique involved toxic mercury
as the
electrode.
Wachsman and his research colleagues have also published details
in Science on a potential path toward SOFCs that operate at temperatures
as low
as 350 degrees C with a new design that features high - conductivity electrolytes and a specially nanostructured
electrode.
Despite these challenges, Moritz thinks that smaller
electrodes, smart engineering — such
as floating
electrode arrays under the skull — and advances
in wireless technology could provide an answer to paralysis
in as little
as 10 years.
Just
as Edgerton's device activated the rats» nervous systems, Harkema's rechargeable and programmable device would tell the
electrodes connected to the dura how much electricity to apply to neurons
in the lower spinal cord, and how often.
During this split second of surprise,
electrodes in the cap register a cascade of electrical impulses known
as a P - 300 response.
Batteries that have solid - state electrolytes work
in high temperatures, but the electrolytes don't connect
as well with
electrodes, which hurts performance.
They also printed vertical
electrodes in a cavity,
as well
as lines of copper.
Or the positioning of the
electrodes might have been partially to blame:
In a separate study, which began after the BROADEN trial, Mayberg and colleagues discovered that they could improve response rates — by as much as 80 % in 24 patients — by fine - tuning the electrodes» positio
In a separate study, which began after the BROADEN trial, Mayberg and colleagues discovered that they could improve response rates — by
as much
as 80 %
in 24 patients — by fine - tuning the electrodes» positio
in 24 patients — by fine - tuning the
electrodes» position.
Instead of creating a sugar molecule,
as they would
in a spinach leaf, the electrons passed through the semiconductor and into the
electrode.