#Precision optics deliver next-gen endoscopes A trio of companies has collaborated to develop a tiny new CMOS imaging module designed specifically for endoscopes.
The resulting objects are an environmentally friendly and sustainable alternative to the metals and plastics that currently dominate 3d printing.
Two different metals, a anode and a cathode are submerged into different solutions and are connected by a salt bridge to form a reaction,
#Scientists Create Liquid Metal Antenna By placing an electrical potential across the interface between liquid eutectic gallium and indium and an electrolyte,
Dr Adams and his colleagues found that they could cause the metals to spread by applying a positive voltage
or to contract by applying a negative voltage. sing a liquid metal that can change its shape allows us to modify antenna properties more dramatically than is possible with a fixed conductor,
and elongate a filament of liquid metal and change the antenna operating frequency. Applying a small positive voltage causes the metal to flow into a capillary,
while applying a small negative voltage makes the metal withdraw from the capillary. he positive voltage electrochemically deposits an oxide on the surface of the metal that lowers the surface tension,
while a negative potential removes the oxide to increase the surface tension. These differences in surface tension dictate which direction the metal will flow,
Dr Adams explained. his advance makes it possible to remove or regenerate enough of the xide skinwith an applied voltage to make the liquid metal flow into or out of the capillary.
We call this lectrochemically controlled capillarity, which is much like an electrochemical pump for the liquid metal.
Although antenna properties can be reconfigured to some extent by using solid conductors with electronic switches
the liquid metal approach greatly increases the range over which the antenna operating frequency can be tuned. or eutectic gallium-indium monopoles with lengths between 75m and 4m, the measured resonance frequency tunes from 0. 66 GHZ to 3. 4hz for a tuning
%which, while lower than a conventional monopole, presents a tradeoff between efficiency and versatility that is evident in most tunable systems. ur antenna prototype using liquid metal can tune over a range of at least two times greater than systems using electronic switches,
And Doesn't Metals, which conduct electricity, and insulators, which don, are polar opposites. At least that what wee believed until now.
On the other hand, electrons in conducting materials such as metals flow freely over long distances. So how can you possibly get electrons behaving in both ways in a single material?
which the bulk itself behaves both as a metal and an insulator. Crystal clear? The material we explored is a well-known insulator that has been studied
and magnetisation a property known as uantum oscillations Such quantum oscillations are inherently a property of metals,
it was also severely violating the rules for conventional metals. Explaining the inexplicable How can we resolve the apparent contradiction inherent in a material that is both a metal and an insulator?
One possibility is that, contrary to current understanding, electrons in certain insulators can somehow behave as if they were in a metal.
This behaviour may involve the strange properties of quantum mechanics. According to quantum mechanics, particles can occupy two states at the same time.
In this way, the strange behaviour of our material could be explained by the fact that wee discovered a new quantum state that fluctuates between being a metal and an insulator.
Our discovery of a material that is neither a conventional metal nor a conventional insulator could be such an mergentquantum phase of matter.
decades of conventional wisdom regarding the fundamental dichotomy between metals and insulators are likely about to be turned on their head.
heating the metal to 1, 500 degrees Celsius (2, 732 Fahrenheit) before melding it into place.
because vanadium is a transition metal with various oxidation states which can be exploited to reach higher capacities.
and metal, has a special superconducting property at very low temperatures and could play a central role in the development of future electronics."
not only in the semiconductor and the metal, but also in the transition between the two very different components,
"In its current state, the metal is a passive material, meaning we need to introduce other elements that will help us control the elastic waves we send to it,
#Laser-generated surface structures create extremely water-repellent self-cleaning metals Super-hydrophobic materials are desirable for a number of applications such as rust prevention anti-icing or even in sanitation uses.
-and nanoscale structures to give the metals their new properties. This work builds on earlier research by the team in which they used a similar laser-patterning technique that turned metals black.
Guo states that using this technique they can create multifunctional surfaces that are not only super-hydrophobic but also highly-absorbent optically.
Guo adds that one of the big advantages of his team's process is that the structures created by our laser on the metals are intrinsically part of the material surface.
And it is these patterns that make the metals repel water. The material is so strongly water-repellent the water actually gets bounced off.
Unlike Guo's laser-treated metals the Teflon kitchen tools are not super-hydrophobic. The difference is that to make water to roll off a Teflon coated material you need to tilt the surface to nearly a 70-degree angle before the water begins to slide off.
You can make water roll off Guo's metals by tilting them less than five degrees. As the water bounces off the super-hydrophobic surfaces it also collects dust particles
It currently takes an hour to pattern a 1 inch by 1 inch metal sample
but ultra-short laser pulses to change the surface of the metals. A femtosecond laser pulse lasts on the order of a quadrillionth of a second
Guo is keen to stress that this same technique can give rise to multifunctional metals. Metals are naturally excellent reflectors of light.
That's why they appear to have a shiny luster. Turning them black can therefore make them very efficient at absorbing light.
The combination of light-absorbing properties with making metals water repellent could lead to more efficient solar absorbers--solar absorbers that don't rust
but often breathe compounds based on metals--typically forms of solid iron. Scientists had witnessed previously decreasing concentrations of uranium in groundwater
So just like bacteria pick up resistance to things like antibiotics and heavy metal toxicity, this bacterium"picked up a genetic element that's now allowing it to detoxify uranium,
He and his colleagues therefore came up with the idea of investigating a compound consisting of the transition metal niobium (Nb
typically platinum and iridium, two rare and costly metals. But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1. 5-volt battery.
is actually more stable than some commercial catalysts made of precious metals.''We built a conventional water splitter with two benchmark catalysts, one platinum and one iridium,
A wide range of reactive or conductive metals can be used, including platinum, gold, and palladium.
"We can stack metals on insulators, too, embedding different functional properties and interactions within one lattice structure."
""The material we studied is an unconventional semiconductor made of alternating atomically thin layers of metals
"CMOS, or complementary metal-oxide-semiconductor, is based the silicon technology used to make transistors in microchips.
the various intermediary steps in the production process still require metals and produce waste.""The KU Leuven researchers developed a new technique."
and without using metals. In addition, the production process is cheaper, because we can skip a step."
#Cancer drug 49 times more potent than Cisplatin Based on a compound of the rare precious metal osmium and developed by researchers at the University of Warwick's Department of chemistry and the Warwick Cancer Research Unit,
The embedded metal ions in the Ni1-xcuxcr2o4 spinel system cause a distortion of the crystal structure.
The research by the lab of Rice physicist Emilia Morosan has already been cited as a textbook example of how magnetism arises in metals.
when the metal is cooled to 36 kelvins, about minus 395 degrees Fahrenheit.""Magnetization is a function of temperature,
Tiau is only the third known itinerant magnetic metal made with no magnetic elements. The other two, both ferromagnets that activate their magnetic order at temperatures even colder than Tiau
They also allow for handy things like electrical conductivity in metals. Atomic moments in local-moment ferromagnets--that is, common magnetic materials--align all of their spins in the same direction.
#Metal foams capable of shielding X-rays, gamma rays, neutron radiation Research shows lightweight composite metal foams are effective at blocking X-rays, gamma rays and neutron radiation,
The finding means metal foams hold promise for use in nuclear safety, space exploration and medical technology applications."
"This work means there's an opportunity to use composite metal foam to develop safer systems for transporting nuclear waste, more efficient designs for spacecraft and nuclear structures,
Rabiei first developed the strong, lightweight metal foam for use in transportation and military applications. But she wanted to determine
The most effective composite metal foam against all three forms of radiation is called"high-Z steel-steel
so that the composite foam that included tungsten was not denser than metal foam made entirely of stainless steel.
"However, we are working to modify the composition of the metal foam to be even more effective than lead at blocking X-rays
In addition, the extraordinary mechanical and thermal properties of composite metal foams, and their energy absorption capabilities, make the material a good candidate for various nuclear structural applications
may act as a sponge that safely binds a metal that can damage brain tissue when it's in excess.
It also wraps around the metal in a way that prevents it from producing free radicals.""Given these properties and its relative abundance,
This is because silver is a precious metal and relatively expensive, and silver particles with nanoscale dimensions oxidise particularly rapidly;
or the interaction between light and free electrons on a metal's surface. When exposed to light
is a popular metal for this plasmonic photothermal heating because it is so efficient at absorbing light.
#Laser-generated surface structures create extremely water-repellent metals Super-hydrophobic properties could lead to applications in solar panels,
sanitation and as rust-free metals Scientists at the University of Rochester have used lasers to transform metals into extremely water repellent,
-and nanoscale structures to give the metals their new properties. This work builds on earlier research by the team in which they used a similar laser-patterning technique that turned metals black.
Guo states that using this technique they can create multifunctional surfaces that are not only super-hydrophobic but also highly-absorbent optically.
Guo adds that one of the big advantages of his team process is that he structures created by our laser on the metals are intrinsically part of the material surface.
And it is these patterns that make the metals repel water. he material is so strongly water-repellent,
Unlike Guo laser-treated metals, the Teflon kitchen tools are not super-hydrophobic. The difference is that to make water to roll off a Teflon coated material
You can make water roll off Guo metals by tilting them less than five degrees. As the water bounces off the super-hydrophobic surfaces,
but ultra-short laser pulses to change the surface of the metals. A femtosecond laser pulse lasts on the order of a quadrillionth of a second
Guo is keen to stress that this same technique can give rise to multifunctional metals. Metals are naturally excellent reflectors of light.
That why they appear to have a shiny luster. Turning them black can therefore make them very efficient at absorbing light.
The combination of light-absorbing properties with making metals water repellent could lead to more efficient solar absorbers solar absorbers that don rust
which rely on the use of noble metals such as gold and silver, the new metamaterial is compatible with the complementary metalxideemiconductor manufacturing process used to construct integrated circuits.
#New catalyst process uses light not metal for rapid polymerization A team of chemistry and materials science experts from University of California,
This new method of radical polymerization doesn involve heavy metal catalysts like copper. Their innovative, metal-free ATRP process uses an organic-based photocatalyst
How can we do this without any metals? said Craig Hawker, director of the Dow Materials Institute at UCSB. e looked toward developing an organic catalyst that is highly reducing in the excited state,
but the new metal-free rapid polymerization process ushes controlled radical polymerization into new areas and new applications, according to Hawker. any processes in use today all start with ATRP.
They were then able to gently scrape some of the silver to leave behind two islands of metal as electrodes, with a strip of silicene between them.
the team is also considering the use of other metals, such as zinc and magnesium that could serve as the anode in a battery of this type. e also expect that other organometallic compounds with multi-valence-state metal centers (redox centers) may also function as the anode,
In the normal non-superconducting phase, the electrons in most metals move independentlyhe scattering of electrons causes electrical resistance.
rare-earth metals are, as their name suggests, hard to come by. Mining and purifying them is an expensive,
Researchers at the University of Pennsylvania have pioneered now a process that could enable the efficient recycling two of these metals, neodymium and dysprosium.
the two metals need to be separated and remixed before they can be reused. t, in principle, easier to get the neodymium
The process is repeated thousands of times to get useful purities of the rare-earth metals,
Rather than this liquid-liquid method, Schelter team has devised a way to separate the two metals by having neodymium stay dissolved in a solution
enabling the two metals to be separated easily. Once apart, an acid bath can strip the ligand off both metals,
enabling it to be recycled as well. f you have the right ligand, you can do this separation in five minutes,
so it is less likely to fall off before the metals are separated. Further modification of the ligand could enable other rare earths in technology products,
and detected using ferromagnetic metal contacts with a tunnel barrier consisting of single layer graphene between the metal and silicon NW.
The ferromagnetic metal/graphene tunnel barrier contacts used to inject and detect spin appear as blue,
which depend critically on the interface resistance between a ferromagnetic metal contact and the NW.
and compatibility with both the ferromagnetic metal and silicon NW. Using intrinsic 2d layers such as graphene
The use of multilayer rather than single layer graphene in such structures may provide much higher values of the tunnel spin polarization because of band structure derived spin filtering effects predicted for selected ferromagnetic metal/multi
Surface plasmons are confined to the surface of a metal. In order to create wakes through them Capasso team designed a faster-than-light running wave of charge along a one-dimensional metamaterial like a powerboat speeding across a lake.
Previous research has evaluated the use of microneedles made of silicon or metal, but they were shown not to be safe.
Lithium ion batteriescathodes typically contain heavy metal ions like manganese, cobalt or iron, but in lithium air batteries, the much lighter oxygen in a sense acts as the cathode, creating a more efficient design.
Typically, scientists who study these circuits have to choose between injecting drugs through bulky metal tubes
You can use either a paramagnetic metal or a paramagnetic insulator to do it now
#Scientists Stretch Electrically Conducting Fibers to New Lengths An international research team based at The University of Texas at Dallas has made electrically conducting fibers that can be stretched reversibly to over 14 times their initial length and
#Speedy crystal sponges to clean up waste Close up of the metal organic framework crystals. New sponge-like crystals that clean up contaminants in industrial waste
The crystals are made of extremely porous metal organic frameworks (MOFS) and have an internal storage capacity of 7,
trapping large amounts of contaminants including carcinogenic material and heavy metals. CSIRO research team leader, Dr Paolo Falcaro, said the length of time it takes to produce MOFS has been a barrier to their manufacture until now. ee estimated that this process could cut the cost to make MOFS by thousands of dollars for Australian manufacturers,
Heavy metals like mercury, lead and arsenic are released into the oceans through manufacturing and industrial processes.
(which has previously proved useful in cleaning up heavy metals) curled up into a coral-like formation.
#Metal foam provides lightweight radiation shielding Nuclear, space exploration and medical applications abound for low-density, nontoxic structural shielding materials Lightweight composite metal foams can absorb energy from impacts
and block X-rays, gamma rays and neutron radiation, according to a study from North carolina State university. The discovery means the materials could be useful in spacecraft, the nuclear industry and in medicine.
which consist of hollow metal spheres of one metal dispersed in a matrix which can be of the same or a different metal,
for military transport applications. They are mechanically strong, thermally insulative and lightweight, with their structure reducing the density compared with a bulk material,
Her research involved comparing foamsshielding properties against pure lead and the A356 grade of aluminium, metals that are used currently for shielding purposes.
The term High-Z refers to all the metals in the alloy having a large number of protons in their atomic nuclei;
we are working to modify the composition of the metal foam to be even more effective than lead at blocking X-rays
#Researchers Develop Super-Hydrophobic Metal Surfaces Using Lasers Researchers have turned metal surfaces water repellent using femtosecond laser pulses.
Researchers from the University of Rochester have used femtosecond laser pulses to turn metals waterproof or super-hydrophobic.
said, his is the first time that a multifunctional metal surface is created by lasers that is super-hydrophobic (water repelling),
The optical and wetting properties of the surfaces of the three metals were altered by these nanostructures.
According to the researchers, properties they provide to the metal will not deteriorate. The super-hydrophobic properties of the laser-patterned metals are similar to the famous nonstick coating.
The project was financed by The Bill & Melissa Gates Foundation and Air force Office of Scientific research and is published in the Journal of Applied Physics y
< Back - Next >
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011