the group said it had employed ultrafast femtosecond lasers to produce a three-dimensional single crystal capable of guiding light waves through glass with little loss of light.
Crystals, with their highly ordered specific lattice structure, have the requisite optical qualities.""Amorphous waveguides fundamentally lack second-order optical nonlinearity due to their isotropically disordered atomic structure,
"The ability to pattern nonlinear optical crystals in glass is therefore essential for 3d laser-fabrication of PICS to achieve its full potential."
"To pattern crystals in glass, the Lehigh-led group employed femtosecond lasers, whose speed and precision make them useful for cataract and other eye surgeries.
Scientists have been attempting for years to make crystals in glass in order to prevent light from being scattered as light signals are transmitted,
The task is complicated by the"mutually exclusive"nature of the properties of crystal and glass. Glass turns to crystal when it is heated
says Jain, but it is critical to control the transition.""The question is, how long will this process take
and will we get one crystal or many. We want a single crystal; light cannot travel through multiple crystals.
And we need the crystal to be in the right shape and form.""After conducting experiments at Lehigh and at Kyoto University and Polytechnique Montreal,
the group built a single crystal in glass, demonstrated its waveguiding capabilities and quantified its transmission efficiency.
The glass and crystal both were composed of lanthanum borogermanate (Labgeo5), a ferroelectric material.""We achieved quality,
"says Dierolf,"by guiding light from one end of the crystal to the other with very little loss of light."
"We have made the equivalent of a wire to guide the light. With our crystal, it is possible to do this in 3d
so that the wire--the light--can curve and bend as it is transmitted. This gives us the potential of putting different components on different layers of glass."
"The fact that the demonstration was achieved using ferroelectric materials is another plus, says Dierolf.""Ferroelectric crystals have demonstrated an electrical-optical effect that can be exploited for switching
and for steering light from one place to another as a supermarket scanner does. Ferroelectric crystals can also transform light from one frequency to another.
This makes it possible to send light through different channels.""""Other groups have made crystal in glass
but were not able to demonstrate quality, "says Jain.""With the quality of our crystal, we have crossed the threshold for the idea to be useful.
As a result, we are now exploring the development of novel devices for optical communication in collaboration with a major company."
or almost melt, until it is transformed into a crystal.""The unique focus of the femtosecond laser also makes it possible to"write"the crystal inside the glass and not on its surface."
we make use of the fact that a heat current passing through a magnetic material creates a separation of electron spins.
made from electroactive dielectric elastomer, a soft, compliant smart material, can effectively copy the action of biological chromatophores.
"The researchers investigated making bio-inspired artificial skin embedded with artificial chromatophores using thin sheets (five to ten millimetre) of dielectric elastomer--a soft,
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,
a hard plastic core surrounded by a softer silicone rubber shell.""Anytime you have a corner,
""The composite post geometry,"Turner said, "achieves the same effect as the mushroom shape. The soft rubber conforms to the roughness of the surface,
The shortcoming of conventional honeycombs is that they lose their full protective properties after only one impact due to plastic buckling of the material.
the darker the skin's pigment, the more ultraviolet B radiation necessary to trigger the precursor chemicals in the body to produce Vitamin d."
Dr Borg's team at Monash University were able to visualise the crystal structure of the Anapn1 protein for the first time, providing valuable insights.
This natural polymer is an ideal"cocoon"that can stabilize compounds such as enzymes antibodies and growth factors while lending itself to many different mechanically robust formats, said Fiorenzo Omenetto, Ph d.,senior author on the paper and associate dean for research and Frank C. Doble Professor
Omenetto and Kaplan are pioneers in the use of silk as an alternative to plastics. Omenetto's 2011 TED Talk called silk a"new old material"that could have a profound impact in many technical fields.
where one in seven composite fillings fail within seven years and 86 percent of these failures are caused by bacterial infection.
and also allows for the coating of larger plastic carrier surfaces, "Wöll says. Thanks to their mechanical properties, MOF thin films of a few hundred nanometers in thickness can be used for flexible solar cells or for the coating of clothing material or deformable components.
Nanoscale mirrored cavities that trap light around atoms in diamond crystals increase the quantum mechanical interactions between light and electrons in atoms.
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,
The new technique relies on polymer self-assembly, where molecules are designed to spontaneously assemble into desired structures.
Here, an intensely hot laser swept across the sample to transform disordered polymer blocks into precise arrangements in just seconds."
To further exploit the power and precision of LZA, the researchers applied a heat-sensitive elastic coating on top of the unassembled polymer film.
the scientists converted the polymer base into other materials. One method involved taking the nano-cylinder layer
These molecules then glom onto the self-assembled polymer, converting it into a metallic mesh.
A wide range of reactive or conductive metals can be used, including platinum, gold, and palladium.
where a vaporized material infiltrates the polymer nano-cylinders and transforms them into functional nanowires.
"We can stack metals on insulators, too, embedding different functional properties and interactions within one lattice structure."
allowing it to drive polymer self-assembly even on top of complex underlying layers. This versatility enables the use of a wide variety of materials in different nanoscale configurations."
"says Yet-Ming Chiang, the Kyocera Professor of Ceramics at MIT and a cofounder of 24m (and previously a cofounder of battery company A123).
Smart polymers were developed first several decades ago, but multiple functions have not been combined effectively in the same material,
an ionic electro-active polymer (i-EAP), which bends or swells with the application of voltage and are used in soft robotics;
and a two-way shape memory polymer (SMP), which can be programmed to adopt and later recall specific shapes, in a type of muscle memory.
Making IPNS has been tried before with a type of plastic known as a block copolymer, but it has been difficult to fine-tune their exact structure because of difficult synthetic procedures.
In this case the researchers were able to use phase separation combined with ordinary polymer syntheses to achieve the complex structures.
"Our artificial neuron is made of conductive polymers and it functions like a human neuron, "says lead investigator Agneta Richter-Dahlfors, professor of cellular microbiology."
and Steven P. Levitan, Ph d.,John A. Jurenko professor of electrical and computer engineering, integrated models for self-oscillating polymer gels and piezoelectric micro-electric-mechanical systems to devise a new
so Bosch focussed instead on bottom-up techniques such as the thermal decomposition of silicon carbide, and chemical vapour deposition onto metal surfaces.
who in the case of their magnetic sensor settled on hexagonal boron nitride. This is for reasons of both cost and technical performance.
whereas with the boron nitride and graphene device the figure is 7, 000. That is a two orders of magnitude improvement.
continuously becomes commercially available in North america Indigo-Clean#is a light fixture manufactured through an exclusive licensing agreement with the University of Strathclyde in Glasgow, Scotland,
Indigo-Clean#was unveiled just before the annual meeting of theassociation for Professionals in Infection Control and Epidemiology (APIC) in Nashville."
"Indigo-Clean#represents a breakthrough in helping to reduce HAIS, "said Jim Hawkins, CEO of Kenall."
"Indigo-Clean#uses a narrow spectrum of visible indigo-colored light at an output of 405 nanometers (nm) on the light spectrum.
The ability of Indigo-Clean#to continuously treat the air as well as hard and soft surfaces,
Indigo-Clean#is automatic and continuous.""As an innovator in healthcare lighting and a leader in LED lighting and controls, we can bring healthcare providers this effective,
""The material we studied is an unconventional semiconductor made of alternating atomically thin layers of metals
""Our goal was to develop an eco-friendly herding molecule as an alternative to the current silicone-based polymers,
and duration by creating a gel with 3d microscopic structures of a polymer compound called polyethylene glycol (PEG) that resembles"reservoirs."
"CMOS, or complementary metal-oxide-semiconductor, is based the silicon technology used to make transistors in microchips.
Compared to other polymers like plastics, the wood nanomaterial is biocompatible and has relatively low thermal expansion coefficient,
Ma's team employed silicon nanomembranes as the active material in the transistor--pieces of ultra-thin films (thinner than a human hair) peeled from the bulk crystal
They have been able to make further chemical modifications to the pores of the 3dom hydrogels by grafting with organic compounds and polymers.
such as responsive materials, organic-inorganic composites and bioactive hydrogels for digestion or separation of bio (macro) molecules s
to pass through two separate"quantum dots"--small crystals that have quantum properties.""If we could detect a superconducting current,
#Producing biodegradable plastic just got cheaper, greener Biodegradable drinking cups or vegetable wrapping foil: the bioplastic known as polylactic acid (PLA) is already a part of our everyday lives.
And yet, PLA is considered not yet a full alternative to traditional petroleum-based plastics, as it is costly to produce.
Researchers from the KU Leuven Centre for Surface Chemistry and Catalysis now present a way to make the PLA production process more simple and waste-free.
which in turn is a building block for polylactic acid. PLA degrades after a number of years in certain environments.
PLA is also one of the few plastics that are suitable for 3d printing. However, PLA is not yet a full alternative for petroleum-based plastics due to its cost.
The production process for PLA is expensive because of the intermediary steps.""First, lactic acid is fed into a reactor and converted into a type of pre-plastic under high temperature and in a vacuum,
"Professor Bert Sels explains.""This is an expensive process. The pre-plastic--a low-quality plastic--is broken then down into building blocks for PLA.
In other words, you are first producing an inferior plastic before you end up with a high-quality plastic.
And even though PLA is considered a green plastic, the various intermediary steps in the production process still require metals and produce waste."
"The KU Leuven researchers developed a new technique.""We have applied a petrochemical concept to biomass,
"says postdoctoral researcher Michiel Dusselier.""We speed up and guide the chemical process in the reactor with a zeolite as a catalyst.
and without using metals. In addition, the production process is cheaper, because we can skip a step."
Of course, PLA will never fully replace petroleum-based plastics. For one thing, some objects, such as toilet drain pipes, are meant not to be biodegradable.
And it is not our intention to promote disposable plastic. But products made of PLA can now become cheaper and greener.
#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,
They can also be used to communicate through objects, such as steel that electromagnetic waves can't penetrate."
"Speakers and microphones both use diaphragms, typically made of paper or plastic, that vibrate to produce
2015 at a lab on KAIST's campus. They used high-frequency magnetic materials in a dipole coil structure to build a thin,
with each coil having a ferrite core and connected with a resonant capacitor. Comparing to a conventional loop coil,
The ferrite cores are designed optimally to reduce the core volume by half, and their ability to transfer power is unaffected nearly by human bodies or surrounding metal objects,
#Crystal structure and magnetism: New insight into the fundamentals of solid state physics A team at HZB has carried out the first detailed study of how magnetic and geometric ordering mutually influence one another in crystalline samples of spinel.
To achieve this, the group synthesized a series of mixed crystals with the chemical formula Ni1-xcuxcr2o4 in
They discovered through neutron scattering experiments at BER II not only how the crystal structure changes, but also uncovered new magnetic phases.
and as heat-resistant and magnetic materials. The embedded metal ions in the Ni1-xcuxcr2o4 spinel system cause a distortion of the crystal structure.
In addition, they also display magnetic moments due to the geometrical structure that cannot be oriented as they otherwise would be.
The exciting thing about this series of mixed crystals is that nickel or copper atoms sit at
what are referred to as tetragonal sites of the crystal structure. Due to their different configurations of electrons, these tetrahedra become elongated along the crystallographic c-axis for nickel,
The distortion of the crystal structure can thus be controlled, which in turn has an effect on the magnetic ordering.
Manfred Reehuis and Michael Tovar were successful in determining the structural and magnetic properties for each of the mixed crystal specimens over quite a wide temperature range,
This shows that the crystal structure is cubic (three right angles three equal edges) at high temperatures, since the kinetic energy of the atoms still suppresses the Jahn-Teller effect
and thereby prove there is a relationship between the conditions for magnetic ordering and the crystal structures.
especially when they are in a geometrical system like a crystal, rather than in isolation,"says Michael Tovar v
A number of polymer structures were tested for their ability to deliver DNA into two rat glioma cell lines.
Among the many polymers tried, the one known as PBAE 447 was found to be the most efficient in delivering the HSVTK gene into the cultured rat glioma cells.
#Polymer mold makes perfect silicon nanostructures Using molds to shape things is as old as humanity.
In the Bronze age, the copper-tin alloy was melted and cast into weapons in ceramic molds.
In a breakthrough for nanoscience, Cornell polymer engineers have made such a mold for nanostructures that can shape liquid silicon out of an organic polymer material.
whose lab previously has led the creation of novel materials made of organic polymers. With the right chemistry, organic polymers self-assemble,
and the researchers used this special ability of polymers to make a mold dotted with precisely shaped and sized nanopores.
Normally, melting amorphous silicon, which has a melting temperature of about 2, 350 degrees, would destroy the delicate polymer mold,
which degrades at about 600 degrees. But the scientists in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
The researchers found the polymer mold holds up if the silicon is heated by laser pulses just nanoseconds long.
but the melt duration is so short the polymer doesn't have time to oxidize
They essentially tricked the polymer mold into retaining its shape at temperatures above its decomposition point.
This could lead to making perfect, single-crystal silicon nanostructures. They haven't done it yet,
Discovery of single-crystal silicon--the semiconductor in every integrated circuit--made the electronics revolution possible.
It took cutting single crystals into wafers to truly understand silicon's semiconducting properties. Today, nanotechnology allows incredibly detailed nanoscale etching, down to 10 nanometers on a silicon wafer.
Semiconductors like silicon don't self-assemble into perfectly ordered structures like polymers Do it's almost unheard of to get a 3-D structured single crystal of a semiconductor.
porous nanomaterials using specially structured molecules called block copolymers. They first used a carbon dioxide laser in Thompson's lab to"write"the nanoporous materials onto a silicon wafer.
contained a block copolymer, which directed the assembly of a polymer resin. Writing lines in the film with the laser,
the block copolymer decomposed, acting like a positive-tone resist, while the negative-tone resin was left behind to form the porous nanostructure.
That became the mold.""We demonstrated that we can use organic templates with structures as complicated as a gyroid, a periodically ordered cubic network structure,
"To study this, the researchers used their technique, ultrafast electron crystallography. The technique, a new development--different from Zewail's Nobel prize-winning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scales--allowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change
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.
In an antiferromagnet, the atomic moments align in opposite directions. Morosan said it's important to know these extremes in magnetic behavior."
"At the heart of the new technology is a piece of nano-engineered silica glass with ions that fluoresce in infrared light when a low power laser light hits them.
"The composition of thermoplastic and fiberglass resins and fibers used in the panels are stronger per-unit density than the steel used in many current shelters
The team working on the safe room developed a steel frame that holds the panels, and the frame can be broken down
but they have the strength equivalent to steel, "said David Cooper, P. E s. E.,president of Cooper Structural Engineers."
The most effective composite metal foam against all three forms of radiation is called"high-Z steel-steel
"and was made up largely of stainless steel, but incorporated a small amount of tungsten. However the structure of the high-Z foam was modified
so that the composite foam that included tungsten was not denser than metal foam made entirely of stainless steel.
but was much better than bulk materials--even bulk steel--at blocking low energy gamma rays. Similarly
"The team created phosphorene by repeatedly using sticky tape to peel thinner and thinner layers of crystals from the black crystalline form of phosphorus. As well as creating much thinner and lighter semiconductors than silicon,
The experimental setup consisted of small patches of graphene (a two-dimensional single-sheet form of pure carbon) sliding against a DLC-coated steel ball.
The microscopic arrestin-GPCR crystals which his team had produced painstakingly over years, proved too difficult to study at even the most advanced type of synchrotron, a more conventional X-ray source.
Measuring just thousandths of a millimeter, the crystals--which had been formed in a toothpaste-like solution--were oozed into the X-ray pulses at LCLS,
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;
Encapsulation by AZO crystals Subsequently, Göbelt used an atomic layer deposition technique to gradually apply a coating of a highly doped wide bandgap semiconductor known as AZO.
AZO consists of zinc oxide that is doped with aluminium. It is much less expensive than ITO and just as transparent,
This process caused tiny AZO crystals to form on the silver nanowires, enveloped them completely, and finally filled in the interstices.
Quality map calculated Measurements of the electrical conductivity showed that the newly developed composite electrode is comparable to a conventional silver grid electrode.
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.
which makes polymer products more pliable and is still in use. igher everyday exposure levels were associated with menopause coming,
The Harvard team solved these problems by using a mesh of conductive polymer threads with either nanoscale electrodes
Neurons ook at this polymer network as friendly, like a scaffold he says. The next steps will be to implant larger meshes containing hundreds of devices, with different kinds of sensors,
they developed a 3-D printing process that uses two types of polymers: one rigid, one flexible.
The printer inserts an array of the rigid polymers into a bed of squishy material composed of the more flexible type.
its naturally smooth surface takes on a patterned texture that depends on the spacing and shapes of the embedded rigid polymers.
its rigid polymers are stuck in a fixed array and cannot change positions relative to one another.
For example, by using elongated rigid polymers instead of spherical ones, scientists could create surfaces that are smooth along one direction but ridged in the opposite direction.
Some rigid polymers might yield differently textured surfaces depending on the strength of the applied force.
but further compression would cause the polymers to rotate relative to one another, creating a different topography.
Other polymers could swell or shrink relative to the soft material. In the sample Guttag and Boyce printed to physically test their code,
the rigid polymers were about a centimeter in diameter and the bed of soft material was about a meter across.
As the former Arizona governor and U s. Secretary of the interior Bruce Babbitt told Propublica:""There is enough water in the West
The Shanghai composite was down 7. 4 percent, and the Shenzhen composite plunged 7. 9 percent.
Share prices in Hong kong, which is regulated separately, also weakened, dropping 1. 8 percent. Analysts had been warning for months about the risks of a stock market bubble in China,
The Shanghai composite is down about 18 percent from its June high J
#This Injectable Brain Implant Can Record and Stimulate Individual Neurons For those who need them most,
#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
so Bailie did it manually. e used a sheet of plastic with silver nanowires on it, he said. hen we built a tool that uses pressure to transfer the nanowires onto the perovskite cell, kind of like a temporary tattoo.
The BAT key enabling technologies include a novel aerodynamic design, custom-made composite materials and an innovative control system.
The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,
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